You can connect an iPad to any Soundfreaq and stream audio via Bluetooth.
The Sound Step, Sound Step Recharge, Sound Stack, and Sound Rise will dock iPads that have the 30-pin Dock connector. The Sound Platform requires an adapter cable to charge (at a reduced rate) and play through the dock. Amazon has several such dock extender cables available.
While Sound Kick does not have a dock, it can stream audio from iPad via Bluetooth and charge iPad via USB. The same goes for the Sound Spot.