Home Screen, Menu Key, Settings, More, Battery. A list of the battery drain percentages. The top name is the largest battery drain. My list shows Screen at 52% of the battery drain. For me the Auto brightness setting is bad. Best is to set fixed brightness at as low a level as workable and change setting if your in bright sunlight. Buying a smart phone with very large screen means large battery drain. My second item is Maps at 19%. I did use Maps. Obviously the highest % users are the items to investigate for reductions.
One way to get Apps usage is the app GSam Battery Monitor, available on Google Play for free. When I select that I get a list. One of the items listed is App Usage. It lists all apps and their % usage down to 0.1%. Go thru the list and choose what is using battery and you don't use the app. Go to Application Manager, select the app and Force Stop. I find shutting down unused apps is worthwhile. Some factory stuff will restart itself but most will stay off. You can also investigate individual app settings, background settings, blah, blah. Choose no sound alerts or simple short sound. Battery drain is impacted by low/noisy signals from the cell towers, WIFI availability. Airplane mode will give you a clue to how low can you go when phone idle. Probably easier to buy a second battery.
Ray