how to integrate phonegap bluetooth api in nsbasic/app? i want to use bluetooth to print
You'll need to use a PhoneGap plugin. There are a number of them for BT:
Keep in mind that most BlueTooth printers have their own set of control codes. You'll probably need a BT library specifically for the printer.
If you don't know where to start, do read this query -- https://discuss.nsbasic.com/t/how-to-use-bluetooth-ble-via-phonegap-or-etc/421 -- and look at the Q & A underneath (note the mention of Samples, and check out the links).