I had a similar problem and kept removing all the programs/widgets/etc. with any hint of a battery drain connection but I would still drain a full battery in about 4/5 hours when off WiFi, even if it was in my pocket the entire time. What finally fixed it was deactivating my SipGate account. I have not yet tried to reactivate it with different settings to see if it is possible to use this without a pocket full of batteries, but for now my battery life is very good.