Its an old RF R/C toy car that i convert it to Bluetooth R/C controled from a smartphone with an aplication that i made with MIT App Inventor. For the movements i use the smartphone's internal orientation sensor and some buttons to turn on/off the lights, to activate the horn, to change "gears" and to connect to bluetooth module of the car.
For the car i removed all the electronics exept the motors and i installed 6 new AA 1,2V rechargable NiMh 1900mAh batteries. I designed new electronics based on Arduino with a HC-05 Bluetooth module and two h-bridge ic's. The L293D for steering motor and the L298N for forward/backward motor. For both ic's i connected parallel the channels, 1 with 4 and 2 with 3.
I will try to upload soon some schematics and code.
Thank you Kostas Kokoras