Best Casino Apps in Australia

29 October 2026 · Verified against the ACMA’s formal-warning register and the Interactive Gambling Act 2001 (Cth).

A real-money casino app you can legally install on a phone in Australia does not exist. The Interactive Gambling Act 2001, in its amended form since 2017, makes it an offence to provide online casino games or online pokies to a person physically in Australia, and no state or territory issues a licence for them. What reaches an Australian phone under the heading of “casino app” is always an offshore product — a site the ACMA has, in many cases, already told Australian ISPs to block. The angle this page takes is consequence: what the prohibition means for the person who installs one anyway, and the order in which the cost of that decision shows up.

Best Casino Apps Australia: Checking Offshore Crypto Costs

Crypto at an offshore casino sounds like the cleanest way around the rule. There is no Australian bank in the loop, no card processor to block the deposit, no merchant category code to trip a Westpac gambling block. Bitcoin, Ethereum, a handful of stablecoins — the casino takes them, the wallet signs the transaction, the chain settles it. What the player has, in the end, is speed.

What follows, in order, is this. The first thing a player gives up is the only person with any obligation to help them: their bank. ANZ’s gambling block operates at the card level, so a crypto deposit on an exchange funded by a card may still hit the merchant category code and be refused. Once the coin is in a self-custody wallet, though, no Australian institution can freeze it, reverse it or trace where it went. AUSTRAC’s threshold-transaction-report rule applies to physical cash of A$10,000 or more — a rule that applies to cash, not to chain transfers, regardless of the amount sent. Crypto at the wallet level is outside the bank and outside the rule.

The second consequence is that there is no Australian intermediary to complain to when a withdrawal stalls. PayID, the addressing layer sitting on top of Australia’s New Payments Platform, warns specifically that a PayID attached to an illegal gambling site is almost certainly a scam. PayID shows the registered account name before the transfer is sent — a small, deliberate friction built into the system. Crypto has no equivalent step. There is no name on the receiving end, no operator behind the wallet, no body the player can write to once the balance stops moving.

The third consequence, and the one most players never read past, is what an offshore operator’s licence actually says. The Interactive Gambling Act does not punish the player; it punishes the provider. The provider is offshore, in a jurisdiction whose regulator does not recognise the Australian player as a person with standing. A complaint to that regulator is a complaint from a non-resident against a licensee of theirs, and most offshore regulators will simply tell the player to seek local advice — advice which, in Australia, amounts to “this product is not licensable here.” The Australian Competition and Consumer Commission has no jurisdiction over an operator licensed in Curaçao. The eSafety Commissioner has no route to a Maltese-licensed casino’s payout queue.

The fourth consequence is the one that arrives last and costs most. H2 Gambling Capital’s 2025 estimate puts Australian losses to illegal offshore sites at about A$3.9 billion a year, with the share of gambling going through legal Australian channels falling from 74 per cent in 2021 to 64 per cent. The market for illegal play is not a marginal curiosity; it is more than a third of every gambling dollar an Australian spends, and almost none of it is recoverable once lost.

Crypto does not fix any of that. It removes the friction that would have stopped the player from depositing in the first place, and the friction it removes is the only friction in the system that protects them.

The rails an Australian bank will and won’t let you reach

The Australian payments stack is built in a way that puts friction around gambling at every licensed gate and almost none around it at the offshore one. The interesting part, for a player weighing which rail to use, is which frictions are statutory and which are voluntary.

Start with what is statutorily off-limits. Under amendments to the Interactive Gambling Act that took effect on 11 June 2024, an Australian-licensed wagering service — a sports bookmaker, a TAB, a lotteries operator — cannot accept payment by credit card or any credit-related product. That covers the card network itself, and it also constrains a wallet like Apple Pay sitting on top of a credit card. Penalties reach A$247,500 for an operator who takes one. Digital currency is in the same restricted list. The list is the law, not a choice, and a licensed bookmaker taking a credit-card deposit from a PayID-linked wallet is breaking it.

What remains open at the licensed end is debit card, bank transfer, PayID over Osko, and BPAY. PayID and Osko are both products of Australia’s New Payments Platform, which became accessible to the public on 13 February 2018 and is owned by New Payments Platform Australia Ltd, a non-profit whose 13 shareholders include the Reserve Bank of Australia and the major banks. A transfer between participating banks on Osko settles in under a minute, twenty-four hours a day, seven days a week. The platform’s monthly outages are contractually capped at two minutes. PayID is the addressing layer on top: more than 25 million PayIDs were registered on the platform as of April 2025, available at over 100 Australian financial institutions.

BPAY is the older bill-payment channel, launched on 18 November 1997 and now operated by Australian Payments Plus (AP+), the same entity that runs PayID and Osko. A payer types the Biller Code and the Customer Reference Number from a bill into their own bank’s online banking. It is available at over 140 banks and financial institutions and is offered by over 95,000 businesses. Since September 2021 AP+ has been the merged holding company for BPAY Group, eftpos and NPP Australia, following ACCC authorisation.

What this adds up to is a deliberate split. The licensed rails — debit card, bank transfer, PayID, Osko, BPAY — sit on top of a payment system whose design assumes the payee is named. AUSTRAC’s threshold-transaction-report rule applies only to physical cash; ordinary electronic bank transfers are not subject to per-transaction reporting, regardless of the size of the transfer. The unlicensed rails at offshore sites — credit cards, credit-linked digital wallets, crypto — sit on top of a system whose design assumes nothing about who is on the other end. The first set protects the player; the second set does not.

The voluntary frictions add a second layer. Westpac’s gambling block works at card level: it refuses authorisation of transactions registered under the merchant category code “Betting/Casino Gambling” on eligible personal credit and debit cards. ANZ’s gambling block, activated in the ANZ app, does the same and extends the block to a digital wallet like Apple Pay used through an eligible card. Once an ANZ customer turns the block on, removing it requires a 48-hour waiting period — a designed-in pause. Commonwealth Bank offers a gambling lock on eligible cards via the CommBank app, with the same non-guarantee: most gambling transactions will be stopped, but the bank cannot promise all of them. None of these blocks is a complete barrier. They are friction, and friction is the only protection the system has.

By the end of 2025, Apple Pay, Google Pay and Samsung Pay collectively accounted for around 45 per cent of all card payments in Australia by number. The Reserve Bank’s July 2025 review proposes removing surcharges only on eftpos, Mastercard and Visa card transactions, leaving American Express explicitly outside the proposed ban — a reminder that American Express, founded as a freight-forwarding company in 1850 and a card issuer from 1 October 1958, runs as a three-party scheme rather than the four-party model Visa and Mastercard use. Surcharges on Amex remain whatever the merchant chooses to charge. Apple itself does not charge fees to consumers for using Apple Pay in stores, online or in apps; any surcharge is the merchant’s, not Apple’s. Transaction limits and PIN requirements are set by the card issuer or merchant, not by Apple.

The practical result is that the rail a player picks is the strongest single signal of which side of the law the deposit lands on. A debit card or PayID to a licensed wagering service is friction with a regulator behind it. A credit card, crypto, or a wallet loaded with credit to an offshore casino is friction with nothing behind it at all.

What a ‘free’ bonus really takes

A “free” bonus at an offshore casino is the marketing word for a sum of money the casino will let the player stake, attached to conditions the casino writes and the player agrees to. Three numbers describe almost every bonus a player will ever see at these sites, and three things follow from each of them.

The first number is the headline. “100% up to A$500” or “200% up to A$1,000” or “50 free spins on a featured slot.” The headline is a marketing figure and tells the player only the maximum they could receive, not the maximum they will keep. The second number is the wagering requirement: the multiple of the bonus the player must stake before any of it can be withdrawn. Forty times is the typical figure in the offshore segment; some sites write it lower, some write it higher. The third number is the maximum cashout cap, the most expensive term on the page and the one most players skip past. A “A$500 bonus with 40x wagering and a A$100 max cashout” is a bonus that pays out, at most, A$100 of whatever the player wins, no matter how the play goes.

None of those numbers is enforceable in Australia. The provider is offshore, the player is in Australia, and the Interactive Gambling Act says the product itself cannot be licensed here. The conditions the player agrees to are conditions with no Australian body behind them. A complaint to ACMA about a bonus term is a complaint about a prohibited service being offered, not a complaint about a contractual dispute, and ACMA’s role is to act against the provider, not to adjudicate the term.

What follows, in the order it shows up, is this. The bonus is credited. The wagering requirement is the playtime the player must put in to unlock it. The max-cashout cap is the ceiling on what they actually take away. If the bonus is “free spins,” the winnings are typically credited as bonus money with the same requirement and the same cap applied. A player who hits a large win during free spins often finds the win is reduced to the cap on withdrawal, with the surplus removed. The marketing page does not say that. The terms page does, in smaller print.

The point of running the arithmetic is to see what the bonus really buys. A A$500 bonus at 40x wagering is A$20,000 of required turnover before any of it is withdrawable. At a typical slot’s return-to-player in the high 90s, the expected loss on that turnover is the gap between the stake and the return, paid out across the play. The max cashout caps that expected loss in a way the bonus value does not. A player who clears the bonus and wins A$5,000 will receive, on the cap, A$100. The marketing number was A$500; the realised value was A$100. The site keeps the rest.

None of it is recoverable. The legal frame that holds the operator accountable in Australia is described in the section on prohibition below; the short version is that there is no Australian small-claims path to an offshore operator’s bonus terms, no regulator whose job is to read a 40x wagering clause and decide whether it was fair. The product is prohibited, the operator is unlicensed for the Australian market, and the only body that can act against the operator is the ACMA — and ACMA acts by issuing a formal warning, then by asking ISPs to block the site, not by refunding the player.

The endgame is that the bonus is not a free thing the casino gives the player. It is a deferred cost the player takes on, in a currency they cannot later redeem.

How a casino app reaches a touchscreen without an app store

The “app” in “casino app” is a delivery channel, not a different product. What an offshore casino app does is wrap the same website the player would otherwise open in a browser into a piece of software the player installs on their phone. The app then connects to the same backend, the same games, the same wallet, the same bonus terms. The legal picture does not change: the Interactive Gambling Act applies to the provision of online casino games to a person in Australia, regardless of whether that provision is through a browser tab, a downloaded app, or a Progressive Web App shortcut on the home screen.

That distinction — channel versus product — is the thing the prohibition turns on. A phone is a general-purpose computer, and the App Store and Google Play both refuse to list real-money casino apps that target the Australian market for the same reason the ACMA does. Apple and Google enforce their own regional rules, and Apple’s Australian storefront does not carry real-money casino apps from operators without an Australian licence. So the offshore app does not arrive through the official store. It arrives through one of three routes, and each has its own consequence.

The first route is the direct download. The casino sends the player an Android Application Package — an APK file — by email or by a link on its website. The player turns off Google’s “install from unknown sources” guard, downloads the file and installs it manually. The app then behaves like any other app on the phone: an icon, a launcher, a permanent presence. What this means is that the app is no longer subject to the store’s review process. There is no App Store team checking the games inside, no Google Play Protect scanning for malware, no automatic removal if the operator’s licence turns out to be fake. The player has done the store’s job for it, and skipped the part of the job that mattered.

The second route is the mobile web app. The casino’s website offers an “Add to Home Screen” option. The phone creates an icon that opens the site in its own window, without the browser’s address bar. To the player, it looks like an app. To the operating system, it is a bookmark. The practical result is the same product with a different wrapper: the browser’s security indicators are hidden, the address bar is gone, the URL is not visible during play. The friction that would have shown the player a warning, or that would have triggered a phishing alert, is removed by the wrapper.

The third route is the in-store listing in a third country. Some offshore operators list their apps on the App Store or Google Play in jurisdictions where the products are legal — the United Kingdom, say, or Malta — and then instruct Australian players to download them through a foreign Apple ID or by sideloading. The Apple or Google account that downloads the app is, on paper, not in Australia. The player using it is. The legal person on the receiving end of the game’s content is, for the purposes of the Interactive Gambling Act, in Australia. The store’s regional rule and the IGA’s territorial rule are not the same rule, and the offshore operator is using one to circumvent the other.

What follows from all three routes is the same. The player has installed an app that delivers a product the ACMA has, in many cases, already told Australian ISPs to block. The install is not a workaround for the block — the ACMA blocks the website the app connects to, and the app stops working in the same way the browser does. The install is, at most, a way to delay the moment the player finds that out.

The comparison the ACMA’s record already gives you

The ACMA does not rank casino apps. It does not rate them, score them, or compare them on bonus size or payout speed. What it does, under the Interactive Gambling Act 2001, is investigate complaints about prohibited interactive gambling services and, where it finds the service is being offered to Australians, issue a formal warning to the operator. The formal warning is the regulator’s formal view that the operator is breaking the law. It is published on the ACMA’s website and it names the operator and the date.

The table below is the ACMA’s list, in the order the warnings were published. It is not a ranking of casinos and not a recommendation. Every entry is a brand the ACMA itself has named as a prohibited interactive gambling service for Australians. Some have been warned once; some have been warned more than once under different operating companies after the first warning was ignored. The list is what an Australian player should read before installing any of the apps marketed to them.

RocketPlay sits at the top because it is the most recently named. The ACMA issued a formal warning to Pulsup Ltd over Rocketplay.com.au in March 2026, an earlier warning having already been issued to Dama N.V. in May 2022 — the same operator that owned the brand at the time of the first warning, and the same operator named in the May 2022 warning that also covered Bambet, Dazard, Level Up, Rocketplay, Cobra Casino and Wild Tornado. The pattern is the one the table shows in column three: when a brand is warned under one operating company, the operator’s other brands usually appear in the same warning, and when the warning is ignored the brand resurfaces under a new company and gets warned again. RocketPlay is two rounds into that cycle.

Level Up Casino’s single warning, in May 2022, was part of that same Dama N.V. round, and it carries the same consequence: the brand is on the ACMA’s register as a prohibited service for Australians and has been since the original warning. The operator has changed, in some cases, and the licence displayed on the site has changed with it, but the ACMA’s record of the warning has not.

Woo Casino and Spirit Casino are both Dama N.V. brands warned in 2025 — Woo in March, Spirit in May. Dama N.V. is by some distance the operator with the most entries on the ACMA’s formal-warning register, and the consequence of that for a player is straightforward: an operator with that many published warnings has been told, formally and repeatedly, that what it is doing is prohibited.

National Casino, in July 2025, was named under Consolutetish S.R.L., alongside Bizzo Casino. Bizzo Casino had already been the subject of an earlier formal warning to TechSolutions (CY) Group Limited and TechSolutions Group N.V. in 2022, so the brand is on the ACMA’s record twice under two different operators. Ignition Casino, named in the same July 2025 round, was warned under Bamboo Media. Instant Casino was named in February 2025 under EOD Code SRL. Jackbit, in April 2026, was named alongside CasinOK under Ryker B.V. Casino Intense was named in April 2025 under Sterplay Holding Ltd. Sky Crown, with Blue Leo, was named in September 2022 under Hollycorn N.V., and the formal warning remains the ACMA’s published position on the brand.

The “subject support” column on the table is not a confirmation that any of these operators support a payment method, a coin, a game or a licence the player might be looking for. Where the column shows listings, those are listings — directories that carry the operator’s name — not the operator’s own confirmation of what it offers. The “no-data” rows are the honest answer: there is nothing in the ACMA’s record, nothing on the operator’s own page, nothing in a recognised listing that establishes what the operator does or does not support, and a player who needs to know should treat that absence as the answer.

The consequence of the table is that there is no offshore casino app on this list that has not been the subject of an ACMA formal warning, and there is no operator on this list that has not been told, in writing on the regulator’s website, that what it is offering to Australians is prohibited. A player choosing any of these apps is choosing a product the regulator has named. That is the comparison the market will not give them; it is the one the ACMA’s record gives them for free.

The fundamentals of the search

What an Australian is searching inside, when they search for “best casino app,” is not a market of competing products. It is a market with one legal product — licensed online wagering on races and sport, placed before the event, plus lotteries and keno — and a long tail of prohibited products the ACMA has spent the last nine years trying to block.

The numbers that describe the search make the shape of the market legible. The ACMA reported in June 2026 that a total of 1,751 illegal gambling and affiliate marketing websites had been blocked since the first blocking request in November 2019. More than 230 unlicensed gambling services had left the Australian market since enforcement was strengthened in 2017. The H2 Gambling Capital estimate of A$3.9 billion a year in Australian losses to illegal sites, and the fall in the legal channel’s share from 74 per cent in 2021 to 64 per cent, are the same picture read from the other side: a market where the legal offering is shrinking as a share, even as the regulator’s enforcement is expanding.

The legal offering is itself narrow. Online casino games and online pokies cannot be licensed in any state or territory; that is the Interactive Gambling Act 2001 in plain terms. What is licensable is wagering on races and sport placed before the event, plus lotteries and keno. The de facto national regulator for online wagering is the Northern Territory Racing and Wagering Commission, which regulates 52 of Australia’s online bookmakers — including Sportsbet, Bet365 and Ladbrokes — under Northern Territory licences. The commission has no full-time staff and meets once a month in Darwin.

The consumer-protection infrastructure that supports the legal offering has not been built for the illegal one. BetStop, the National Self-Exclusion Register, has been live since August 2023. It binds Australian-licensed online and phone wagering services, so a self-excluded Australian is locked out of every licensed bookmaker in the country. An offshore casino is not connected to BetStop. A self-exclusion registered with BetStop does not extend to a Curaçao-licensed site; the offshore operator has no technical or contractual obligation to honour it. The 1800 858 858 National Gambling Helpline is free, twenty-four hours a day, seven days a week, with chat at Gambling Help Online. None of those services is reachable from inside an offshore casino app.

The consumer side, then, looks like this. There is a regulated core: a small set of products, a single national self-exclusion register, a helpline any Australian can call, and a payments stack designed to slow gambling down. Around it sits an unregulated periphery: offshore casino apps, crypto deposits, instant bank transfers to a wallet whose name the player did not check, and an ACMA block list that grows by roughly twenty-two entries every month. A player choosing between the two is choosing between a product with a regulator and a product with an enforcement record. The first gives them somewhere to complain; the second gives them a regulator who is willing to act, but only against the operator.

Prohibition under the Interactive Gambling Act 2001 — and the cost the player carries

The Interactive Gambling Act 2001 is the only reason the rest of this page is necessary. The Act, as amended by the Interactive Gambling Amendment Act 2017, makes it an offence to provide online casino games, online pokies or in-play betting to a person physically in Australia. No state or territory issues a licence for online casino games. The minimum age for any gambling product in Australia is 18. The Act targets the provider, not the player; an Australian who plays at an offshore casino is not prosecuted, but the site they are playing at is breaking Australian law by offering them the product.

What that means in practice is what the ACMA does, and the order in which it does it. The ACMA investigates complaints about prohibited interactive gambling services. Where it finds a service is being offered to Australians, it issues a formal warning to the operator. If the operator ignores the warning, the ACMA can ask Australian internet service providers to block the site. Blocking is the last step, not the first; the warning is the regulator telling the operator, in writing, to stop. The warning is published on the ACMA’s website and it names the operator and the date.

The blocking-rate band, calculated against the figures the ACMA reported in June 2026, gives a sense of the scale. A total of 1,751 illegal gambling and affiliate marketing websites had been blocked since the first blocking request in November 2019 — roughly 79 months from November 2019 to the ACMA report of 26 June 2026. Spread across that window, the rate works out to somewhere in the range of twenty-two sites blocked every month, between roughly twenty-one and twenty-three depending on which sub-window the count is read over. The cadence has held for seven years. It is not a slow drip; it is the ACMA working at a regulator’s pace.

The most recent published round, on 26 June 2026, asked Australian ISPs to block 12 more illegal gambling websites: 7Signs, ChromaBet, Donbet, Duospin, Freshbet, Slots Gem, Jacks Club, Lucky Start, Pointsbetz.com, Spinrise, Vinyl Casino and Wildsino. That single round is roughly half a month’s worth of blocks at the long-run rate, delivered in one decision. The cadence is not constant; it spikes with rounds and falls in between.

The consequences for a player, in order. The first is that the site is prohibited. The second is that the operator has been formally warned, and the warning has not stopped them, because offshore operators can choose to keep accepting Australian players with no Australian consequence other than a published warning. The third is that the site is blocked at the ISP level, and the player loses access with whatever balance is still on it. There is no compensation mechanism; the ACMA’s role is enforcement, not refund. The fourth is that, if the site resurfaces under a new name, the ACMA warns it again and the cycle continues. Several of the brands in the table above are on their second warning under a second operator.

The credit-card ban, in force since 11 June 2024, is the most consequential payment-side rule. Under the amended Interactive Gambling Act, Australian-licensed online wagering services cannot accept payment by credit card or any other credit-related product. The ban explicitly extends to a digital wallet like Apple Pay loaded on a credit card. Digital currency is in the same restricted list. Penalties reach A$247,500 for an operator who takes one. An offshore operator that accepts credit cards from Australians is not bound by the ban, because the ban applies to Australian-licensed services. The Australian player using a credit card at an offshore site is bound by the issuing bank’s terms and by the bank’s gambling block — and that is the only friction in the system that engages.

The 2026 reform layer sits on top. The Interactive Gambling Amendment (Gambling Reform) Bill 2026 passed Parliament on 19 August 2026; its advertising and inducement measures commence 1 January 2027. It is a law with a start date, not yet in force on a page dated 2026. The effect, once in force, will be to constrain how licensed wagering services market inducements to Australian customers; the ban on providing online casino games remains the central prohibition.

The tax side is a quieter consequence. Recreational gambling winnings of an Australian player are not assessable income, under section 6-5 of the Income Tax Assessment Act 1997, and losses are not deductible — unless the person is carrying on a business of gambling. That is the model only; a player who has any doubt about their own position is reading a guide, not a tax ruling, and the Australian Taxation Office is the body to ask.

What the player is carrying, in the end, is the full cost of an offshore market the Australian legal frame refuses to recognise: a product with no Australian regulator behind it, no Australian complaints body, no Australian recourse if a withdrawal is refused, and a regulator whose response to a complaint is a published warning rather than a refund.

When the product becomes the problem

There is a point at which the conversation about what an offshore casino app offers stops being about offers and starts being about the player. The first hint that it has happened is usually not a number on a screen; it is the moment a player lies about how much they have spent, the moment they hide a deposit, the moment a balance becomes a thing they cannot mention to the person sitting next to them. None of the protections described on this page address that moment. They are addressed by a different set of services.

BetStop, the National Self-Exclusion Register, has been live since August 2023. A self-excluded Australian is locked out of every Australian-licensed online and phone wagering service that is connected to the register. The exclusion can be set for a minimum of three months and is otherwise open-ended, with no maximum period. The register is the national answer to a question the offshore market does not answer, and the question is the one a player asks themselves when they decide they have had enough. The offshore casino the player was at is not connected to BetStop, because the offshore operator is not licensed in Australia. The self-exclusion does not extend, and the only way to make the offshore side stop is to stop using it.

The National Gambling Helpline, 1800 858 858, is free, confidential and available twenty-four hours a day, seven days a week. The line is staffed by counsellors, not by marketers, and a player who calls it is not signing up for an offer. Gambling Help Online carries the same service as a chat, for the player who would rather type than speak. Both services are run by the same network of state and territory organisations, and both are independent of any operator named on this page or any other page.

What follows when a player uses one of those services is the same thing that follows when they use any professional help: an outside view of the situation, a written record, and the first step of a plan that does not depend on the player staying motivated on their own. None of it requires the player to stop gambling that night. The decision to stop, or to cut down, is the player’s, and the service’s job is to make that decision possible to carry out.

The endgame for the offshore app, when it goes wrong, looks like this. The player has a balance they cannot withdraw. The Australian banks have no record of the deposit on the gambling side because the deposit was crypto or a credit card the bank has not flagged. The ACMA cannot refund the player; that is not what it does. The offshore regulator’s process is slow, expensive to access from Australia, and built for a player who lives in the regulator’s own jurisdiction. The player is left with a number on a screen, a customer-service chat that has stopped responding, and a list of services they should have called before they installed the app.

The consequence of the prohibition, taken to its endpoint, is that the offshore app the player installed is the product that becomes the problem, and the services named above are the part of the Australian system that exists to help when it has. The earlier a player reaches them, the less the product has already cost.

Frequently asked questions

Is there any real-money casino app that is actually legal for Australians to use?

No. Under the Interactive Gambling Act 2001, online casino games and online pokies cannot be licensed in any Australian state or territory, and no major app store lists them for Australian accounts as a result. Real-money casino apps available to Australian phones are all offshore products the ACMA treats as prohibited services.

How does an offshore casino app actually reach an Australian phone if the app stores will not list it?

It reaches the phone through one of three routes outside the official store: a direct APK download emailed or linked by the operator, a mobile web app the player adds to their home screen, or a foreign-store listing accessed through a non-Australian account. Each route puts the app outside the store’s review process.

Does installing a casino app get around the ACMA’s website blocking?

No. ACMA blocks are issued to the domain the app connects to, not to the app on the phone. Once the ACMA asks ISPs to block the site, the app stops connecting in the same way a browser does, and any balance left on the account is unreachable from inside the app.

Are the games inside an offshore casino app tested for fairness?

The offshore operator may publish a return-to-player figure or a certificate from a testing lab, but there is no Australian regulator whose job is to verify those claims. The testing, where it exists, is performed by the operator’s chosen lab and reported on the operator’s own terms, and ACMA does not arbitrate disputes over it.

What is the legal alternative for an Australian who wants to play casino-style games on their phone?

There is no legal Australian-licensed casino app for real money. The legal alternative is licensed wagering on races and sport, placed before the event, plus lotteries and keno, accessed through a Northern Territory-licensed bookmaker or a state lottery operator. BetStop, the National Self-Exclusion Register, applies across those licensed services.