I used the free version of this for a few days and my phone did all kinds of wierd things. The battery life was terrible for one, and I have always been one to brag about not having those issues. Sometimes I would have the phone on the charger for hours and it MIGHT increase the battery 1-5%. Other times it would charge as normal. Luckily it was obvious which app was causing this for me. Why? I have no idea. I unistalled it, and it was isntantly better. I re-installed it, and the problems came right back.
The first night I installed this app, I put my phone on the charger at 11pm (like normal). I woke up at 7am, see that the led is green so I unplug it from the wall, and the battery is at 54%. After waking the phone up, I realized it was erroring out on the "end call" screen. Not only was it impossible for me to make a call, but I hadnt made a call to this person since owning the phone. His picture was on the screen like I had just hung up. I couldnt close it, and had to pull the battery.
Sorry for the long post. I dont have a clue why/how this app would cause me those problems, but it was pretty straight forward. Im back to just using Task Manager, and the phone is running perfect again.