Two question on Bluetooth development on Android:
Is there a way to enable Bluetooth to be always on (I might have a long device discovery phase in my applicati
Enabling Bluetooth to be always on, may not be a good decision, if your only concern is long discovery delay ("battery life"-wise).
As for third-party Bluetooth APIs, the only thing that I've heard of is iAnywhere Blue SDK (from Sybase, not free, only evaluation version available), which covers some of the features, that will be supported in the future from the system/bluetooth and bluez packages.
According to the Android's Bluetooth roadmap, most of the long waited things like Java API, Bluetooth 2.1 + EDR will be implemented, at one point in the future.
Good luck with your project.