There are nearly as many slots developers as there are casinos at which to play games.
Some have been around for decades, cutting their teeth in Vegas casinos or the pubs and clubs of the UK and Australia. But in 2017, all have survived to offer great online and mobile slots for real money.
The old hands now do battle with a generation of slick online software operators. The new kids on the block stuff their games full of exciting bonus features, 3D graphics, animations, and colour. They even tie up with Hollywood studios and TV companies to bring out top branded slots for the mass market.
While picking a slots site is important, it's also key to do your homework on the developers themselves.
It's the software developers that make online casinos possible. Understanding them a bit better can only improve your online experience. You'll learn what a quality developer is from this page, what the software developers do to make casinos good and why good quality software can make such a very real difference when you play online.
Onlineslots.com looks at the top online software developers of casinos and games, describing what makes each unique and a valuable player in the online casino industry.
Some developers started life producing physical slot machines for land-based casinos. They may have pioneered the first mechanical or video slot games before moving into online slots.
Newer developers have come in during the 2000s when online slots were in full swing. They keep producing top titles throughout the year and adapt their new releases for the growing mobile market.
But all online slots developers should possess a valid gaming license when they release games. Stories have emerged of some quite respected developers hacking into their own games to make them pay out more favourably to friends and family. A decent license means that the software and game math behind the games have been checked and verified for fairness.
Where there's a respected slots developer there's a respectable online casino stocking their games. Good casino sites will only buddy up with the best developers who deliver every time. Some casinos enjoy exclusive partnerships with the developers. So, if you want to try out that brand new progressive slot, you'll have to sign up for a real-money account with that one casino.
Let's take a look at some of the biggest slots developers working right now.
Some online casinos have exclusive deals with a specific software developer, while others will utilize three, six, 10 or more developers. Neither is better than the other, with the former providing players with some unique and exclusive gaming choices and the latter a wide range of variety.
Microgaming began producing slots and casino games in the mid-1990s. In fact they were responsible for the first ever online casino software. More first came a few years later when the Isle of Man-based manufacturer brought out the world's first progressive jackpot slot - Cash Splash. The game is still enjoyed at hundreds of Microgaming online slots sites today.
More recently, Microgaming has hit the headlines for offering games with life-changing jackpots. The Mega series of slots includes titles like The Dark Knight, Mega Moolah and Mega Moolah Isis. In a world record in 2015, a British player hit The Dark Knight's progressive for £13.2 million, proving just how popular Microgaming's slots continue to be.
Microgaming's big rival is Playtech, the Israeli gaming firm launched in 1999. Like Microgaming, Playtech has branched out into online poker, but slots are still what the firm is best-known for.
While slick 3D titles like The Three Musketeers and the Queen's Diamond have shown Playtech can compete with the new breed of developer, it's the branded slots and progressives that set the company apart.
The Marvel Jackpot series contains a range of hugely popular titles, all linked by four progressive jackpots. The Incredible Hulk, Iron Man 2 & 3, The Fantastic Four and Avengers feature four jackpots with various seedings. The biggest - the Ultimate Power Jackpot - seeds at $100,000. Playtech also develops successful slots based on popular TV brands like The Sopranos.
The award-winning Scandinavian software developer continues to grow, and gained a license in 2015 to operate online in the US.
Slick 3D games and interesting features are NetEnt's big draw, and the firm's 'Touch' range of mobile slots caters for iOS and Android players. More basic progressives like Mega Fortune still prove popular. Until 2015, NetEnt's Mega Fortune held the world record for an online jackpot when a Scandinavian player won nearly €18 million playing the slot.
NetEnt has also branched out into branded online slots. The innovative, and award-winning Aliens is based on the 1986 James Cameron sci-fi film, while the Scandie firm signed up to release a slot based on the rock band, Guns N Roses, which is now available to play.
Bally has undergone many changes and takeovers over the years. The original Bally started out in the 1930s, and released many pioneering games during the following decades. The 1963 release, Money Honey, is seen as the pre-cursor to many modern land-based casino slots. A move into Las Vegas followed, with acquisitions of small casinos in the gambling mecca. Bally still parades its name over one of The Strip's top casinos.
Bally made history in 1994 with the release of one of the first touch-screen video slots, 'Game Maker', while its 'Thrillions' progressive was (at the time of release in 1999) the biggest progressive slot in America.
Bally still continues to develop slots for land-based casinos in the US, and has adapted many of its popular games for online casinos. Previous offline favourites like Hot Shot, Hot Shot Progressive, and Quick Hit, can be played at many Internet slots sites for real money.
One of the oldest and most well-respected slots developers in the US, IGT has produced some of the biggest slots and online slots in the world.
Cleopatra and Da Vinci Diamonds continue to draw in new customers to online casinos. Da Vinci Diamonds' 'Tumbling Reels' is a much-copied feature in video slots today.
Meanwhile, innovative slots like Siberian Storm (with its honeycomb, 720-ways-to-win structure) are an ever-present in casinos, both offline and on.
Despite buying out rival software firm, WagerWorks, in 2005, IGT was itself taken over by Italian gaming company GTECH in 2014. The move hasn't slowed down IGT's output, with an excellent 'Wheel of Fortune'-based slot based on the Sherlock Holmes movies a recent success.
Based in Austria, Novomatic began life producing machines for casinos across Europe. Their Gaminator cabinets can still be seen in casinos in the UK, US and Europe, and contain up to a dozen top Novomatic slots in one place.
As for popular games, the Egypt-themed Book of Ra is a standout, as are titles like Sizzling Hot Deluxe, Dolphin's Pearl and Lady's Lucky Charm Deluxe. All can be played live, online or on mobile and offer simple thrills with low paylines.
One of the first developers to move into mobile slots, Scandinavian company Play N Go offers great titles with a range of themes. There are over 80 titles in the Play N Go arsenal, and new games continue to be released all the time. Games are available to play in HTML5, making them perfect for the new mobile generation of players.
The Aussie software developer has been around since the dawn of slots, it seems. Producing 'pokies' for pubs, clubs and casinos across Australia, Aristocrat has been making moves into the US market. Aristocrat, as of 2017, operates a few thousand slot machines in North America to go with its Aussie games.
Most of Aristocrat's online output are straight adaptations of their land-based slots. Big Red is dated, but still popular, while games like 5 Dragons and Cash Express can be enjoyed for low stakes at bigger online casinos.