I have read that it is better to set the Thunderbolt screen brightness to about 40% to save battery life. Does anyone know if I am better off just leaving it on automatic since the phone would adjust to a lower light setting when needed?
You can test this yourself by using each setting, and going into your Battery Manager to see which uses more battery. On my X, however, I haven't noticed that the Automatic setting uses anymore battery than if I set it myself. I'm sure the TBolt is different, but I can't imagine it would be drastically different.
Everyone probably has different feelings and preferences on this. I have mine set a 25% inside and turn it up to 100% if I need to use it outside. I know 25% sounds pretty low, but it's really looks fine indoors. Automatic should be fine, anything is better than leaving it on 100% all of the time and having it eat your battery. I just prefer more control and knowing what the setting is instead of leaving it up to the auto adjust and not knowing what % it's at. That's one of the great things about Android. I actually have a little control over my phone now. There are a lot of brightness adjustment apps and widgets in the Market. This is the one I use: http://https://market.android.com/details?id=com.curvefish.widgets.brightnesslevel&feature=search_re...
Just an edit to agree with vereyezuhn. I doubt that the automatic setting uses any more battery or memory than one of the apps or widgets, I just have more control with the app.
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.