Using which Bluetooth Module?

Projects General Guidance
1

I wanted to wirelessly control my robot and for that wanted a pass by walls :stuck_out_tongue_closed_eyes: technology and also which should be cheap, i have looked deeper and found this module http://www.rhydolabz.com/index.php?main_page=product_info&cPath=130_132&products_id=454 ,i would want to connect and send commands through a bluetooth 2.0 tech. acquipped Mobile phone.

Connection should be pretty simple in my opinion just needing a tx & rx linking with the Arduino and the Bluetooth module(Module itself powered @ 3 volts [The max it can take!]) , But If i want to send the Word "Start" how i can do that using the Mobile phone?

or if Above one is not capable then what about this BUT is Costlier than even a XBEE - http://www.rhydolabz.com/index.php?main_page=product_info&cPath=130_132&products_id=479

2

You will need a cell phone that supports SPP (serial port profile) Also, that module is SMD and only 3v tolerant so you will need a level shifter and some good soldering skills.