Will throw these thoughts in as mine also died a while ago but then came back up after sitting on the desk for several days....
The oldest question in modern electronics?
1. Is is software (apps)
2. Or hardware?
My 02c worth. the Droid (settings-about phone-battery use) will tell you what the percent of usage is since the last time you powered the phone up. Unless you were running apps, the major contributor is never apps, but whatever you were last doing? If it is an app, mine typically says "screen" If I have been on the phone for a while, it will say "phone usage"
Remember, even though this "about phone" info is background, some consideration should be given to the software that provides this info.
Now when MY phone died, it simply would not come back up? So I could not asscertain exactly what was causing the problem. But based on the full charge that morning, something must of taken the battery way down to the point that no reboot was possible????
My take, based on bookoo electronic experience is that when the DROID(any embedded electronics) fails to boot up or "Come Alive" its not the use of an application but rather, the main CSCI (application software) seeing something that it did not like so it just plain shuts down. Typically these are hard failures of built in tests, but then again maybe not? When my phone came back up it was after sitting for days, then (just by chance) I tried the charger again and it came "alive" I still have definitive answers, and can only assume base the previous assumptions on the way older (slower) embedded electronics was developed.
Regards,
Bo