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The MOGA PRO POWER Controller is a Bluetooth wireless controller for Android. It features a flip-up clip that holds phone of nearly any size.
SpecsUpdate
Pros
Pro Foldable arm lets you game on-the-go
The front part of the controller folds out into an arm. This makes gaming on the go extremely convenient. The arm can fit a phone with a maximum width of 3.2" (82mm). Your phone will most probably fit in there even with a case on.
Pro Very comfortable to hold and well balanced
The MOGA Pro Power is a full sized controller, just like a PS3 or XBox gamepad. Most Android controllers are smaller, which makes them more cramped and uncomfortable for longer use. A larger controller fits your hands better, making it more comfortable. Since you can place your phone on the unfoldable arm, it helps balance the phone's weight better so it isn't as top-heavy.
Pro Dual wireless profiles
It has both the MOGA profile and the generic HID profile for greater overall support.
Cons
Con Connection can be flaky at times
Users have reported that the controller sometimes disconnects when other bluetooth devices are active at the same time, or when playing for extended periods of time.