iOS 5.1.1 is the highest iOS the 2010, 1st generation iPad can go. The 1st generation iPad was, more or less, an early adopter model iPad. It was underpowered with only 256 MBs of RAM and NO cameras for image/video shooting or FaceTime calling. If you have a newer iDevice, install the newer version of the app to your newer iDevice first. More @Wikipedia
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