Yes, this problem would be best addressed by finding the app that's keeping your phone awake. You should check all the apps that run and/or refresh periodically in the background. For example twitter client, email client, todo list, things like that. Try and set the refresh rates to longer periods, see if that helps at all. If not, you might need the help of a task manager app to check which processes are running in the background, if there is any of them that use the processor all the time. But please, DO NOT start killing every process or app you come across, find the one that's causing the problem and change its settings! To help you along the way, A\C has a great guide on proper task killing (or rather, not doing it at all, if possible), please read it here.
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