The iMpulse gaming controller for your mobile that fits on your keyring

Gaming on a tablet or smartphone is fun, but it can also be frustrating when sliding around the touch controls. Controller options are plentiful but nothing was truly portable, until the iMpulse.

The iMpulse is sold as the smallest portable controller you can buy. Despite being small enough to fit on your keyring it doesn't scrimp on specs. You'll get a full D-pad and the usual four buttons plus another on the front. And it also crams in two trigger-like buttons on the rear.

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On top of control offerings, the iMpulse also features Bluetooth connectivity and a battery that will keep going for nine hours of continuous play.  And it works on both Android and iOS devices.

While we would imagine the small size might make it feel like a GameBoy, our hands aren't as small as they were when we played that last, so this may get a bit "crampy" for longer sessions. But for $40 (£25) and the ability to attach this controller to your keyring so you never forget it, we'd say it's money well spent.