Review: Kyocera Echo
Apps
Most applications from the Android Market will work on the Echo. When used in Single Screen mode, it behaves as any other Android device, so you're covered in that respect. As mentioned earlier, there are only a few apps that support the Simul-Task and Optimized modes. They are already on board, and I didn't see any more in the "Echo Top App" tool on the Echo. Presumably more will become available over time. Any Android app will work in the tablet mode, which essentially just stretches everything out to fill the screen.
Bluetooth
The Echo can connect with mono and stereo Bluetooth headsets with no problems. I didn't encounter any issues when pairing different devices, though sound quality through both mono and stereo headsets was miserable. The Echo can also be used to push pictures (and other files) between devices, such as PCs or other phones.
GPS
The Echo offers two options for directions: Google Maps and TeleNav. Both are free. I enjoy Google Maps and think it does a great job of providing directions. TeleNav is a solid alternative, though, and Sprint doesn't charge for its use. Both will get you from here to there with no problems. The TeleNav app also offers voice commands, though they only worked about half of the time.