How do I determine which process woke up the screen?
Download the GSam Battery Monitor (formally knows as Bad Ass Battery Monitor)  it will keep track of the number of times and for how long each app keep the device awake.

Open GSAM and go to the App Sucker view (icon on the lower left). Then change the view to Time Held Awake.  To see the number of time an app held the device awake press on the app.


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