Hello Punith,
I would like to recommend the Kinetis K70 120/150 MHz MCUs.
The Kinetis K7x is a Low-power MCU with graphics LCD, connectivity and security.
Please find more information about this family at the following link:
http://www.freescale.com/files/32bit/doc/fact_sheet/KNTSK70FS.pdf
Using the UART or SPI module from the device mentioned, it can communicate with an external Bluetooth device chip.
Hope this information will be useful for you.
Have a great day :smileyhappy:
David Diaz