I haven't had any luck with recorder apps with the Motorola Droid RAZR MAXX.
Google Voice can record calls. The problem is keeping the same phone number. Since I am on Verizon's network and not Sprint's, I would have to port my number. Not going to do that and terminate my contract. Instead, I just give people my Google Voice number instead.
Not what you were looking for but hopefully someone will find one.