Big Time Gaming slots on mobile

Big Time Gaming slots on mobile: what you need to know first

Big Time Gaming (often shortened to BTG) is a small Australian studio with an outsized footprint. Its Megaways engine, which changes the number of symbols on each reel every spin, became one of the most copied ideas in modern slots, and the studio still releases its own Megaways, cluster and fixed-ways games. You'll find more studios like it in our slot providers hub.

On a phone, BTG games behave like any other modern slot. The casino app opens the game in its own window, the reels adapt to the screen, and the information panel holds the paytable, the rules and the return to player (RTP) for the version that casino runs. Nothing about the phone itself changes the odds.

Two things set BTG apart for mobile players. First, most of its titles are volatile, so a £20 session can end quickly or run long depending on when a bonus round lands. Second, several of its best-known games were built around feature options that UK players don't see, which we explain in the rules section below.

Who is Big Time Gaming? The Sydney studio behind Megaways

Big Time Gaming was founded in 2011 and is based in Sydney, Australia. Nik Robinson is its chief executive, and he is the name most often linked with the creation of Megaways. The studio's early catalogue was small, but games such as Bonanza, Extra Chilli and White Rabbit turned it into one of the better-known game providers in UK casino lobbies.

In April 2021 a deal was announced for Evolution to buy the studio. Evolution (opens in a new tab) is best known for live dealer tables and game shows, so BTG became its slot arm alongside other studios. One visible result is Extra Chilli Epic Spins, a live game show launched by Evolution in April 2023 that puts the Extra Chilli Megaways reels in front of a studio host. The live side of the group has its own coverage on our site.

Megaways licensing to other studios

BTG didn't keep Megaways to itself. A CasinoBeats report on the Blueprint deal (opens in a new tab) records that Blueprint Gaming became the first licensee on 1 May 2018, and Diamond Mine followed that month. Gambling Insider's coverage of the Red Tiger agreement (opens in a new tab) describes the mechanic as patented in the US and the name as a trademark, licensed to Red Tiger in October 2018.

Those deals explain why you see the Megaways logo on games from so many studios. Dragon Born is generally cited as the first Megaways game, though trade reports from 2018 give slightly different launch dates for it, so we don't state one here.

How Megaways works on a phone screen

A Megaways reel shows a random number of symbols on each spin, usually between two and seven. Wins pay left to right on adjacent reels, and the number of ways to win is simply the symbols on each reel multiplied together. That's why the counter above the reels jumps around from one spin to the next.

The arithmetic is easy to check. Six reels each showing seven symbols gives 7 × 7 × 7 × 7 × 7 × 7 = 117,649 ways, the figure on Bonanza and Extra Chilli. Five reels of up to seven symbols, as on Kingmaker, gives 7⁵ = 16,807. A fixed 6×4 grid, as on Danger High Voltage and Lil Devil, gives 4⁶ = 4,096 ways every spin.

More ways doesn't mean better value. The RTP is set by the game's maths, not the ways count, and a spin with 117,649 ways can still pay nothing. On a small screen the bigger issue is legibility: a tall seven-symbol reel shrinks each icon, so many players turn the phone sideways. Our guide to landscape and portrait mode in casino apps covers that choice, and the wider Megaways slots on mobile page looks at the format beyond BTG.

Big Time Gaming slots compared: RTP, volatility and max win

The table below lists the main BTG games we review, each linked to its full mobile review. RTPs are the published headline figures; casinos can run lower versions of some games, so the number in your app's help screen is the one that counts.

Extra Chilli's often-quoted 96.82% includes Feature Drop, a bonus buy that isn't offered in Great Britain. The GB version without it is listed at up to 96.41%, and versions range from 96.15% to 96.41%.

Danger! High Voltage 2 arrived in 2024 as a Megaways sequel with up to 117,649 ways, a choice of Fire in the Disco or Danger Danger free spins and a listed maximum of 52,980× stake. Its RTP isn't confirmed in the specifications we rely on, so check the game's help screen before playing.

Signature mechanics in BTG slots: Reactions, Extra Reels and Megaclusters

Most BTG games share a handful of building blocks. Once you recognise them, the busy screen of a new release becomes much easier to read on a phone.

Reactions (cascading wins)

In Bonanza, Extra Chilli, Millionaire and Monopoly Megaways, winning symbols are removed and new ones drop in, so one paid spin can produce a chain of wins. BTG calls these Reactions. In the free spins rounds of Bonanza and Extra Chilli, a win multiplier rises by one with every Reaction and doesn't reset, which is where most of the games' upside sits.

The Extra Reel

Bonanza puts a horizontal reel above reels two to five, adding one more symbol to each and making room for a dynamite wild. Extra Chilli and Millionaire Megaways use a similar extra row, and Millionaire's can carry a question-mark wild. On a narrow screen this strip is easy to miss, so it's worth spotting before you start.

Megaclusters and Megapays

Star Clusters Megaclusters applies the idea to a cluster pays grid. It starts as a 4×4 board, and each winning symbol splits into four smaller ones that can form new clusters before fresh symbols fall in. Free spins come from chains of these reactions within one spin. Megapays is the studio's other named mechanic; its workings aren't described in the game specifications we use, so check a game's rules screen for how it works there.

Choose-your-bonus rounds

Several fixed-ways games let you pick a free spins mode. Danger High Voltage offers Gates of Hell, with seven spins and sticky wilds that can extend to 19 spins, or High Voltage, with 15 spins and wilds whose multipliers can reach 66x. Lil Devil gives a similar choice between Be My Angel and Dynamite Lover, and collecting 40 hearts in the base game opens enhanced versions of both.

Megaways slots from other studios using BTG's engine

Many Megaways games you'll meet in a UK app aren't made by BTG at all. They're built by other studios under licence, and their RTP, volatility and features are set by that studio. Two examples with full reviews on our site show how different they can be.

Diamond Mine is a good warning about RTP versions: the same game exists at 96.43%, 93% and 92.01%. That gap is worth real money over time, which is why checking the help screen matters more than the studio name. For the licensees themselves, see our pages on Blueprint Gaming slots, Relax Gaming slots and Red Tiger slots.

What a £20 budget means on Big Time Gaming slots

Slots are entertainment that costs money, and the house edge means losses are likely over time. The RTP tells you the long-run average: the expected loss is your total stake multiplied by (100% minus RTP). It says nothing reliable about one evening, especially on high-volatility games like most of BTG's range.

With £20, you get 200 spins at 10p, 40 spins at 50p or 20 spins at £1, if nothing is won back along the way. In practice small wins get recycled, so you usually stake more than £20 in total before the balance runs out.

Here is a worked example. Two hundred spins of Bonanza at 10p means £20 staked, and 4% of £20 is an average cost of 80p. The same 200 spins at £1 means £200 staked and an average cost of £8. Those are averages across huge numbers of spins: a high-volatility game can just as easily take the full £20 in 40 spins or pay a bonus round worth several times it.

The 2.5-second minimum spin time also puts a ceiling on pace. At most 3,600 ÷ 2.5 = 1,440 spins fit into an hour, so an hour at 20p could mean up to £288 staked and, on a 96% game, an average cost of £11.52. Our high RTP slot apps list covers apps where checking RTP is straightforward.

Playing Big Time Gaming slots on mobile: iPhone and Android

Like most modern slots, BTG games load inside a casino's iPhone or Android app rather than as separate downloads. The casino's app handles your account, deposits and limits; the slot itself streams in when you open it, which uses some mobile data and battery. How much depends on the game and your connection.

Whether a particular game prefers portrait or landscape isn't published for most of these games, and it can vary by casino. Busy Megaways screens are usually easier to read sideways, but try both in the app you use.

How to find a BTG slot and check its RTP in an app

1. Open your casino app and sign in. You must be 18+ and verified before you can play, including demo play.
2. Tap the search in the game lobby and type the slot's name, for example Bonanza or White Rabbit.
3. If the studio name shows on the game tile, confirm it says Big Time Gaming rather than a licensee.
4. Open the game and look for the information or help icon, usually marked with an 'i' or a question mark.
5. Find the RTP line in the rules and note the figure, as some casinos run lower versions.
6. Set your stake before the first spin and decide your budget for the session in advance.

The steps differ a little between apps, so if you can't see the RTP, our guide on how to find a game's RTP in an app covers the usual places to look. Apps don't have lower RTP by default; the version is chosen by the casino, and the same figure should appear on mobile and desktop for that site. Our RTP on mobile explainer goes into more detail.

UK rules that shape BTG slots in casino apps

British slot rules change how BTG games play compared with the versions shown in some overseas reviews. The main ones are below.

• Stake limits: under the Gambling Commission's online slots stake limit guidance (opens in a new tab), the maximum is £5 a spin for players aged 25 and over (from 9 April 2025) and £2 for players aged 18 to 24 (from 21 May 2025). These limits apply to slots only.
• Speed: each spin must take at least 2.5 seconds, and turbo and slam-stop features aren't allowed (since 31 October 2021).
• No autoplay: autoplay has been banned on online slots since October 2021, and on all online casino games since 17 January 2025.
• No false celebrations: a return equal to or lower than your stake can't be presented with win sounds and animations.
• Feature buys: since a Gambling Commission games warning to online operators (opens in a new tab) in January 2020, feature buy-ins are not offered to British players. That's why Extra Chilli's Feature Drop is missing from GB versions.
• Spend display: since 17 January 2025, your net spend and time played must be shown in real time, and you can't play several games at once.

Some BTG games still offer optional gambles inside the game, such as the gamble wheel before Extra Chilli's free spins or Millionaire's Hot Seat quiz ladder. These are part of the game design and are allowed; treat them as extra risk on top of the spin. Full details sit on our slot stake limits and game design rules pages.

Which Big Time Gaming slot suits which player

Every slot here is a cost, not a way to make money, so the choice comes down to how you like a session to feel. These pointers come from each game's published RTP, volatility and features.

• Highest published RTP: White Rabbit Megaways at 97.24%, with expanding reels in free spins.
• Simplest first Megaways: Bonanza, the original, with one free spins round and a rising multiplier.
• Choice of bonus round: Danger High Voltage or Lil Devil, which let you pick between two free spins styles.
• Familiar themes: Monopoly Megaways, made under a Hasbro licence, and Millionaire Megaways with its Hot Seat quiz ladder.
• Something different from Megaways: Star Clusters Megaclusters, with its splitting cluster grid.
• Five reels instead of six: Kingmaker, with up to 16,807 ways and four growing gem multipliers.

If you'd rather compare apps than games, our ranking of the best Megaways slot apps looks at it from the casino side.

Casino apps for Big Time Gaming slots: offers to know

We can't confirm which BTG titles each partner carries at any moment, so search the game lobby of PlayOJO, Coral or Ladbrokes before signing up. Coral's App Store listing mentions Megaways among its slots, and Ladbrokes' listing describes 1,800+ slots. None of the welcome offers below is paid on a Big Time Gaming slot; all are 18+ and terms apply.

PlayOJO: new UK customers (excluding Northern Ireland) get 80 free spins on Big Bass Bonanza with a first deposit of at least £10. Spins are worth 10p each, there's no wagering and winnings are paid in cash. The offer can't be combined with other offers and is only available through the designated offer link.

Coral: from 1 October 2026 to 1 February 2027, new players who deposit and bet £10 or more on slots get 100 free spins on selected games, worth 10p each. Accept them within 48 hours and use them within 7 days; there's no wagering on free spin winnings. Neteller, PayPal, Paysafe, Skrill, prepaid cards and certain debit cards don't qualify.

Ladbrokes: new customers who deposit and spend £10 or more on slots get 50 free spins a day for the first 10 days, up to 500 in total. Spins are worth 10p on selected games, must be claimed before 23:59 each day and last 7 days, with no wagering. Prepaid cards, PayPal, Paysafe, Neteller, Skrill and Moneybookers deposits don't qualify.

The value of 100 spins at 10p is £10 of stakes, and what they return depends on the game's RTP and luck. Coral and Ladbrokes are both run by LC International Limited (Entain), so you may not be able to open new accounts at both.

18+. Every casino game has a built-in house edge, so over time you should expect to lose what you stake. Set a budget before you play and stop when it’s gone: safer gambling tools and support. Free, confidential help: National Gambling Helpline 0808 8020 133.