While Canabalt ($2.99) didn't necessarily invent the side-scrolling running genre, it sure did popularize the approach on the iPhone. Even today, a few years after release, it's still one of the best games on the platform, sending you vaulting from rooftop to rooftop and everywhere in between while aliens attack in the background and debris falls in your path. And the minimal, monochromatic aesthetic still shines.

Building upon the hugely popular approach of its predecessor, Temple Run 2 (free) refines its 3D take on the runner theme, sending you forward into a maze of paths and obstacles that requires you to swipe as needed to turn, jump, and slide. Beyond the impressive visual boost, the sequel also adds new mine cart and zip line sequences to the layouts, bringing some helpful variety to this entertaining chase game.

Humor has been a great hook for some of the better endless runners, and it's definitely at play in the aptly-titled Grim Joggers ($2.99). Rather than command a single sprinter on a path, this amusing entry puts you in control of 20 such runners, which all react at once to your taps. You'll need to time your jumps well to avoid the gruesome fates found in these stages, including spike traps and polar bears.

It's notably more action-packed than the average runner, but Punch Quest (free) finds the right balance between running and bashing skeletons with well-timed uppercuts. It's a runner that you can really dive into, as special powers and character upgrades offer incentive for dedicated play, and the retro aesthetic is a charmer throughout due in large part to its offbeat humor. Laser-spewing velociraptor, anyone?

Sure, the time you spend on the ground in Jetpack Joyride (free) will likely be minimal, but this riotous spin on the runner approach is one of the top iPhone games in any genre. As cartoonish hero Barry Steakfries, you'll attempt to break free from a lab using a stolen, bullet-firing jetpack,all the while evading hazards like electric barriers and rockets. And the ample customization options only add to the fun.

Unlike Temple Run, Into the Dead (free) doesn't force you onto a fixed path with its 3D running gameplay, but that doesn't mean the path is clear. In fact, the open fields ahead are filled with undead, shambling beings that want nothing more than to devour your flesh. This first-person take on the genre impresses with atmosphere, plus you can use weapons and items to help survive longer in the dark.

Extreme air and a colorful aesthetic help give Ski Safari ($0.99) a unique tenor, as you'll attempt to stay on two skis while sliding down the slopes ahead of a raging avalanche. Though you'll start on the skis, the downward path is riddled with friendly penguins, yetis, and more that'll help shepherd you to safety. Whatever your form of transportation, it feels great to grab huge air and spin for seconds before landing.

Robot Unicorn Attack ($0.99) began life as a Flash game, but it's no less mesmerizing on iPhone. Adult Swim's take on the genre merges a strong Lisa Frank visual influence with the repeating backing track of Erasure's 1994 hit "Always," with the result being a game that you can't help but fall in love with. As for the game itself you'll jump and dash alternately to dodge gaps and bash through giant star crystals.

Punch Quest isn't the only tweak on the endless runner that Rocketcat Games is responsible for; Hook Worlds ($0.99) punches up its pixel-packed side-scrolling approach with the use of a grappling hook to glide through levels, with four different worlds each starring a different protagonist. One virtual button lets you swing while the other offers a special ability, making for a very distinct riff on an auto-runner.

Without legs on the large, floating protagonist it's fair to argue that Whale Trail ($0.99) cannot be a runner in the traditional sense. But while this endless side-scroller offers one of the biggest visible alterations of the bunch it's also a blast, thanks in large part to its vibrant aesthetic. Floating amongst the clouds you'll tap and hold to float upwards and dodge evil clouds,all while collecting colorful bubbles.