Mobile gaming is big business. Whether it's defending your garden from waves of oncoming zombies, catapulting surprisingly explosive birds at pig-built structures of questionable integrity or matching up primary-coloured fruits until they dance in front of your eyes for days, it seems everywhere you look on the bus or the train, someone's jabbing at their smartphone screen. Even the prime minister has admitted to being partial to a spot of Fruit Ninja as a stress-relieving mechanism.
But what many of these games have in common is they're designed for a short, sharp blast – ideal for the morning commute, but not exactly the sort of thing you'd settle down on the sofa with for an evening. For most people, the realm of smartphone gaming revolves around simple concepts, collecting coins or gems and that 'just-one-more-level' attitude that usually ends when you look up and realise you've missed your station and are now on a non-stop service to Aberdeen.
However, this isn't all there is. If you're tired of throwing your phone through the window when you fail at Flappy Birds for the millionth time, or are fed up of downloading supposedly free games, only to get a cutesy pop-up begging for money every five minutes, there are options available.
In fact, serious gamers who are looking to break free from the console have more choice than ever. Whether it's ports of classic games or all-new titles designed for the mobile, there are plenty of options available if you want your mobile gaming experience to be a little deeper and more engaging. So with this in mind, here are five of our top paid-for picks.
Grand Theft Auto: San Andreas
Definitely not one for the kids, this port of the open-world crime classic is available on iOS, Android and Windows Phone and lets you wreak havoc across a fictional version of California and Nevada.
Still fondly remembered by many as among the best of the controversy-stoking series, if you can tear yourself away from the mindless destruction, San Andreas offers a lengthy story and employs the voice talents of Samuel L Jackson and James Woods, among others.
Final Fantasy VI
Don't ask how exactly there can be six games claiming to be the 'final' fantasy (the series is up to 14 on consoles and, if nothing else, is good for teaching kids their roman numerals), this classic Japanese role-playing game – originally released back in 1994 for the SNES – now has a new lease of life on Android and iOS.
Widely considered one of the best video games of all time, this might let a whole new audience get sucked into its detailed steampunk world, engrossing multi-hour storyline and complex turn-based battles. If you want a game that lasts more than just a couple of hours, this is it.
Deus Ex: The Fall
The first mobile instalment of the award-winning Deus EX series, The Fall has been on iOS since last year, and came to Android in January. Combining stealth and role-playing elements, what really hits you about this is just how good it looks. You might have to double-check you're not playing a console game, as the developers have really tested the current generation of smartphone technology to see what it's made of.
XCOM: Enemy Unknown
This special-ops themed tactical strategy game, originally designed for consoles in 2012, came to iOS last year and made waves by being one of the first genuinely premium mobile titles – reflecting just how much content you get with it.
Tapping the touchscreen to order your troops around and survey its urban environment is intuitive and makes much more sense than using a controller, so players get a full home gaming experience wherever they are.
Football Manager Handheld 2014
As any armchair Alex Ferguson will tell you, Football Manager isn't so much a game as a way of life. The classic example of the 'just-one-more-turn' compulsion, assembling and managing your team on the incredibly-deep PC version can easily take over your entire thought process, to the point where you can find yourself sketching new formations and tactics wherever you are.
That's why a mobile version makes so much sense and with the 2014 edition, there's even more scope to lose yourself in its labyrinth of leagues, players and stats. Whether it's taking Stoke to Champions League glory, seeing Messi and Ronaldo terrorise defences together or just trying to keep your Conference strugglers afloat, having this time-sink in the palm of your hand means you might never get off a bus in the right place again.