Verizon recently released a system update for the HTC ThunderBolt. Although this update doesn't bump up the Android OS to Gingerbread (2.3), it does appear to have made a significant improvement on battery life. In the past, I was switching to 3G mode all the time because 4G LTE was draining my battery way too quickly. Now, it seems like I can keep it on 4G LTE and the battery is lasting much longer. I'm also not experiencing any problems with random reboots (a problem that was reported in an earlier update that was released, then pulled from Verizon).
For more information about this update, you can visit the Verizon support page here.
Verizon Wireless is pleased to announce a new software update, Build Number: 1.70.605.0 Baseband: 1.39.00.0613w, 0.01.69.0613w_1, for your ThunderBolt™ by HTC.
+ Improved data connectivity.
+ Enhanced Call History view.
+ Reduced number of device power cycles and resets.
+ Improved Bluetooth® Discovery Mode pop-up window.
+ View App Menu in tabbed layout.
+ People search function enabled.
+ Backup Assistant has been added to the All Apps menu.
+ Preloaded My Verizon, V CAST Music and V CAST Videos.
+ Desktop cradle App is now available, showing clock in landscape mode.
+ NY Times site has been added into the browser bookmarks.