This device is EXACTLY what I need for prototyping, it's like they designed it just for me and my thesis. There are only things stopping me from giving it five stars. First, there is no indication for when the battery is charged or when it's low, so it often just shuts down when I'm in the middle of working with it. I've often left it plugged in for hours overnight and it still didn't have enough charge to even turn on by morning. I highly recommend getting an external charger for the battery, it's been a lifesaver for me. The second thing is that even though there is support for developing in the Arduino environment, there is little to no documentation about how to do so - you simply have to dig through the source code to figure it out. Nonetheless, I'm super excited about this device!