Apps may request a WAKE_LOCK to keep a device component from "sleeping", so they can perform a task even when the display is turned off. Obviously, those "Wakelocks" can become an issue for how long your battery's charge holds...
What are WakeLocks?
Quoting from our Master-Question:
Apps may request a WAKE_LOCK to keep a device component from "sleeping", so they can perform a task even when the display is turned off. This is very useful in most cases (e.g. keeping the screen on while navigating, keeping WiFi active to stream music) -- but used in the wrong way, it causes your battery to be drained within short term (up to 25% per hour).
Related tags
- battery-life: obviously when "badly used" wakelocks keep the device unnecessarily awake, this has bad influence on how long your battery lasts with one charge