Digisocial is the latest free iPhone app with ambitions to become its own mobile social network. Instantly familiar in design to anyone who’s used Instagram or Path, Digisocial adds the ability to send and receive HD-quality voice messages, and even record audio to accompany uploaded images. It’s a clever idea that mostly works as promised – the app is fast and responsive at sending text or voice messages, and it’s quite entertaining the first few times you use it. Unfortunately, I can’t help but think Digisocial is just one announcement away from obsolescence, should an existing rival decide to incorporate the same concept.

When Temple Run hit the App Store in summer 2011, it didn't look like much -- no thanks to its pixelated, original PlayStation-level graphics and unremarkable visual design. But the old adage about not judging a book by its cover holds true with free iOS games, as well, as its genre-shifting 3D twist on the traditional side-scrolling runner made it an absolute sensation, racking up more than 170 million downloads in the time since. With new sequel Temple Run 2, Imangi Studios needn't worry about making a bad impression, thanks to dramatic visual improvements and welcomed gameplay enhancements.

A dark, moody atmosphere and a mysterious safe filled with complex puzzle-box curiosities lie at the heart of The Room, an enthralling puzzler that balances intrigue with challenge. Much like a set of Russian nesting dolls, cracking the outer shell of the massive iron box awaiting in the center of this grim abode only leads you deeper down the rabbit hole of mechanical conundrums to solve. Locked in single room and left with a peculiar note hinting at the powerful artifact tucked away within the huge safe, your task is to unravel the winding puzzle-filled path to this ancient device.

Joe Danger was a pleasant surprise when it premiered on the PlayStation 3 back in 2010, mixing challenging vehicular platforming with the oh-so-addictive pursuit of the highest score. Since then, the cartoonish motorcycle stuntman has received a sequel and special edition on the Xbox 360. But the series' latest iteration and first on iOS, Joe Danger Touch, manages to ride wheel-to-wheel with its console predecessors, creating a new experience ideally suited for the platform.