The pi Mount gets its moniker from the shape of the design. When viewed from the front, the design looks like the mathematical symbol for pi. The legs of the symbol are perfectly sized to squeeze the Apple iPhone power adapter when it's plugged into a wall socket. On top of the pi is a channel that's wide enough to hold an iPhone clothed in a thin case (no, it won't hold an iPhone 4S in a mophie juice pack air, thank you very much).
The idea here is simple: instead of laying your iPhone on a kitchen counter or other surface where it could be splashed by a tipped glass of wine or knocked onto the floor, get it up off of that surface and onto the wall. While you're at it, give your iPhone a quick charge!
In practice, the pi Mount takes no time to install, and the design makes placement of the AC adapter, the mount and the iPhone intuitive. My only complaint is that the charging cable just hangs there, which still creates a hazard for pulling the cable out of the iPhone and having it drop. This could be easily remedied if the pi Mount folks could get a short 9-inch USB cable manufactured that would be just long enough to go from the AC adapter USB socket to the connector on the iPhone.
Still, I love the design and execution of this simple accessory, and at $9 (with free domestic ground shipping), buying one is a no-pain proposition.
Alton Brown would probably not be pleased with my appraisal of this one-task device, but the pi Mount does one thing very well: it gives you a place to put your iPhone when you're charging it.
Dirt cheap, but well-constructed
Cleverly designed and works with any iPhone in most bumpers and thin cases
Cable still dangles; I'd pay another $5 for a really short charging cable for use with the pi Mount.
Who is it for?
Any iPhone owner who has wished for a way to keep their charging phone off of a countertop or floor.