which is the best tool to monitor my cars OBD II?

ok so i wanna be able to see whats going on inside my cars OBD , i wanna be able to see temps, fuel pressure, if the car is running on an open loop or a close loop, mainly this last one the open or close loop. i wanna able able to see that so my question is whats the best or whats a decent tool monitor all this things or how can i tell if my car is even going from a close to an open loop.