Android class providing access to the system alarm services.
Timertask is a Java API class
"Alarmmanager should also be more efficient than timertask"
from question "How to place a thread with and infinite foor loop inside a background service"
"Alarmmanager consumes lesser battery power than timertask or thread"
from question "Android force kill schedule service every minute"
"Hence the alarmmanager which runs much better than a java timertask thingy"
from question "Run GPS listener in background on Android"