I am a cell phone technician and I have found that the Android Advanced Task Killer generates a lot of problems. First, it is counterproductive, in that it is always running, therefore pulling on the battery. That also takes back the CPU speed quite a bit. Most customers with the app experience a lot of lag, freezing, and force closes. Also most Android phones are on the 2.3 OS (Gingerbread) or 2.2 (Froyo) and have built in task killers. Some phones can even have a program monitor as a widget.