My "normal usage"
Music using earphones - 1 hour
Games - 20 mins
Videos - YouTube about 10 mins
Surfing using chrome browser/email - 1 hour
SMS/whatsapp - dunno how to gauge this but quite frequent
Calls - approx 20mins
Camera - about 10 photos and playing around with photo sphere for 5mins
With my S2, doing all these stuff will not last more than 12 hours, so i feel the nexus 4 battery life is good enough.
Settings
Auto brightness off. Brightness about half
Bluetooth off
NFC off
GPS off
Wifi always on
Silent mode when zzz
Email I set manual update (never push)
sounds like how i use my phone (still using ip4), even though people say my phone is almost like an old dumbphone with whatsapp

