There's a long-held belief in gaming that simple games are best, and there's certainly some truth to that.
Having depth is fine, but present any gamer - whether a dedicated, grizzled, unnervingly scary veteran or someone who plays the odd casual game on an iPhone - with a focused, playable, highly intuitive gaming experience, and addiction is almost guaranteed. This is especially true if the gameplay mechanics are tight and the presentation is top-notch, all of which explains the success of Tiny Wings.
Fundamentally, there's really not much to Tiny Wings. The entire screen is a button, which makes a bird retract his stumpy wings and dive-bomb. Let go and he unfurls his wings and flaps for all his might.
The key to success is in the timing - you prod when the bird is over a hill's downward slope and while he's sliding, and you let go when he's on an upward slope and soaring through the air. There's plenty of randomness in Tiny Wings, due to the way levels are generated procedurally, but there's skill in the timing.
And because the game is easy to learn, it's more of an equaliser than the likes of Complicated New 3D Shooting And Exploring Game VII.
The basic mechanics behind Tiny Wings aren't new, though - they're the distillation of ancient platform games such as Pitfall! and Hunchback. But instead of you being able to move your character and leap or duck to avoid a hazard (the hazard in Tiny Wings, in case you're wondering, is landing in the wrong place), the game automates movement, leaving you to concentrate solely on timing.
This focused, honed-down dynamic has been used by a number of iOS games that have built on these basic foundations to create new and instantly playable games.
One of the most famous - and the title that kick-started the endless genre - is Canabalt (£1.79, universal). Originally a Flash game, Canabalt made the leap to iOS and wowed gamers with its tiny running man leaping across rooftops.
The grim colour scheme and moody soundtrack made it feel like a dystopian take on exaggerated parkour, and wonderful touches - jet engines slamming into rooftops, flocks of birds flying as you pass, buildings crumbling underfoot - distract from what is ultimately a limited (if playable) one-note game.
Today, it's tough to recommend Canabalt outright, not because it's poor, but because many other games have taken the basic formula and improved it beyond measure, often by way of simple add-ons.
Some integrate arcade-style double-jump mechanics, enabling you to jump again while plummeting towards failure; others include extra gestures, for sliding under obstacles or punching things out of your path; and a sub-set of titles add weaponry, turning games into two-thumb challenges where you off foes while avoiding falling to your death.
The weapon add-on is particularly popular. Our favourite game of this kind is Halfbrick'sMonster Dash (69p, universal), which has time-travelling hero Barry Steakfries battling his way through exotic locations, blasting demons, mummies, vampires and yetis to oblivion.
The game retains Canabalt's endless nature, but multiple environments (Steakfries teleports every thousand metres) and weapons add longevity, even if the lives system (you get three) only assists when colliding with foes - fall to your death and your game's instantly over.
Rogue Runner (free, iPhone) deals with that problem, mercifully enabling you to continue after death-dives. Although its jump mechanic feels a bit floaty, it's a good choice for anyone who's exhausted Monster Dash, not least because the selection of themes and characters is huge.
Another option with varied content is Air Supply (£0.69, iPhone), set on alien worlds and boasting sharp retro styling, although its unlock mechanic to access new content is disappointingly gruelling.
Some games ditch guns for more tactile weaponry. Angry Rhino Rampage (69p, iPhone), Robot Unicorn Attack (69p, iPhone; £1.19, iPad) and Lame Castle (69p, iPhone) all use charges to smash objects away. The first two games are 'cartoon cute' and 'bizarre kitsch', respectively.
Robot Unicorn Attack is particularly oddball in having you guide a robot unicorn through a pastel landscape while being serenaded by 1980s pop group Erasure.
Lame Castle, though, is the standout; there's a mix of finite and endless modes, with you guiding a knight on a hobby horse to rescue his love from the titular lame castle, punting chickens along the way in an amusingly Phythonesque manner.
I Must Run (69p, iPhone) dials down the humour but ups the intensity and adds further gestures; the protagonist's Canabalt-like escape takes him over rooftops and on speeding subway trains, requiring you to swipe to duck, and tap to punch and jump - simple actions that become surprisingly easy to forget when you notice a bridge approaching your head at 100mph.
The logical conclusion of such games is ultimately found in the gloriously bonkers Run! (69p, iPhone) - which lets you karate-kick sharks in the head and repel alien invasions with a trusty pocket bazooka (not a euphemism) - or EA's somewhat more traditional platform game Mirror's Edge (59p, iPhone; £2.99, iPad), which isn't endless but uses similar controls to I Must Run.
Elsewhere, further smallish changes to the template lead to unique endless gameplay experiences. Dino Rush (69p, Universal) is akin to a prehistoric Angry Rhino Rampage, but multiple taps make the fruit-munching hero fly; this action expends energy, making the game about risk versus reward, a theme also fundamental to the wickedly funny Grim Joggers (£1.49, Universal).
That game has a troupe of joggers determinedly making their way through hostile territory, regularly falling prey to spike-pits, explosives, polar bears and aliens. Having a string of crazy people to control makes proceedings frenetic, although, surprisingly, not any easier than Canabalt or Tiny Wings from a progress and survival standpoint.
And if you're still gagging for more, you could try vermin doing gnarly stunts in Rat On A Skateboard (69p, iPhone); intense neon gravity-flip madness in DOT5URBO (free, iPhone); or a climbing ninja, leaping between two towers in Ninjump (free, iPhone and iPad).
If you want to mix things up a bit, you could try the odd bit of swinging instead of jumping in Hook Worlds (69p, iPhone), which offers four separate modes that can be roughly described as: swinging; swinging plus guns; swinging plus gravity-flipping; and swinging plus ludicrously difficult and retro.
It's great fun, as is the rather simpler MrAahH!! (69p, iPhone), which almost provides the opposite experience to Tiny Wings, challenging you to land on a central spot or fall to your doom while going "aaaaahhhhh".
Finally, with the amusing and cute penguin-on-ski-slopes dive-bomb leaper Pilot Winds (free, iPhone), we're back where we started with Tiny Wings, having leapt, punched, unicorned, chicken-punted, flipped and swung through over a dozen great but simple games.
First published in Tap! Issue 05
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