Other than the fact that it is very hard to set if you don't use the app, I used to love this - UNTIL it suddenly stopped working with both our IPhone 4S phones. Now, no matter what I do, I get the message that this accessory is not supported by this iPhone. Now it is useless.
I got one of these from a big-box retailer and both of the top docks stopped charging my devices after only 2 weeks, only the USB port still charges. (iPad 2, iPhone 3GS) I am returning it. Additionally, it is awkward and difficult to connect the iPad onto its dock, it rests only on the connector and the rubber support and is not stable from side to side.