Yes Whatsapp is a battery killer, makes your phone hot, since I uninstalled it my phone only felt barely warm under continuos internet browsing.
What it did is hijacked the music app and trick the phone to keep sending some small data in seconds interval (streaming) to keep the wifi on so people will get the message fast. This is to cater mainly for people that don't have data plan to fall back on after the lock screen cut off the wifi connection (mainly wp7 users now since wp8 portico can keep wifi on, but why use whatsapp if you don't have data plan on phone -.-" ) Even if you tab back to close it, it is not off and continue to run, if you press the volume button, the music player button will appear and if you press play it will bring you to whatsapp.
Skype still in Beta, people reported with battery draining issue too, but there are also people stating that after reinstall it is ok.
Some battery apps will also cause battery drain because of the continuous polling.
Feb 25 2013, 03:56 PM
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