Neal, i usually get a FULL day out of my phone with no problem.. all depends on how you manage it. I have learned to leave 4g off and that is the big thing. Verizon doesnt have 4g in all locations yet so when you leave the antenna on for 4g it killllls the battery while it is CONSTANTLY searching for those towers. Drop it to 3g and your golden it lasts all day. "IF" you need that speed boost you can jsut turn it back on. I use a app called Phone Info that can be found in the market that makes that a very simple task I cant say anything bad about the thunderbolt with the only exception it does not come stock with swype however swype beta which is downloadable from them works great