Dear Chris, the Android Central article was interesting.
(Play store has around 10 apps named close to AppLock. I assume you mean the one from "domobile.com" with 1 million downloads. "The most downloaded app on play store".) It seems that the important features are already part of the new Android.
Android has a max of 10 minutes to keep the screen on. I was constant ly entering my pin. The play store apps that kept the screen on used up the battery quickly. I tried about 5 of them. Finally I started swiping a pattern instead of using a pin. This is less secure, but fast enough that I can stand it.
Thanks again for your help. Any other comments?