We are thermal printer manufacture based in India (Mumbai) . we have perfect solution on your requirement please see the following link.
http://www.maestroselectronics.net/PrintingSolutions/Products/2bluetooth_printer

we also provide the sample apk file to you , and the SRC code to integrate printer with your application . If you want more information please contact on following details 

Thanks & Regards,
Sachin Nikam

Sales & Marketing Executive 
Maestros Electronics and Telecommunications Systems Ltd
EL 44, TTC Industrial Area, Electronic Zone, Mahape,
New Mumbai - 400710 (INDIA)
Tel: +91 - 022-41193100/200
Mob: 09167630149
 
http://maestroselectronics.net/