During my research for the best speaker dock, I discovered that there are that many iPad docks available. The new trend to produce devices that only allow bluetooth connections, and thus lack a real docking feature.
Here are some reliable speaker dock that still allow you to dock your iPad and immediately play your music:
Sony RDPXF300IPN Lightning iPad Dock
The Sony RDPXF300IPN Lightning iPad Dock is the best sounding speaker dock I’ve tested. The two speakers output 20 watts each, and have a rich and bright sound. In fact, this dock sounds better than the Bose SoundDock Series III (which also lacks bluetooth connectivity and a remote control).
This dock has an internal lithium-ion battery so it can be used as a portable player, it also features a radio and a remote control.
The Sony RDPXF300IPN Lightning iPad Dock is available from Amazon for about $300.
iHome iDL48BC Dual Charging Portable Rechargeable Speaker
The iHome iDL48BC is available from Amazon for about $80.