We know you've got questions, and if you're brave enough to ask the world for answers, here's the outlet to do so. This week's Ask Engadget inquiry is coming to us from Chuck, who seems to be having an unusual level of difficulty getting his phone through an entire day on a single charge. If you're looking to send in an inquiry of your own, drop us a line at ask [at] engadget [dawt] com.

"I have the HTC Evo, which has terrible battery life. I've gone through many steps, including rooting it and using SetCPU, however I'm still not getting as much out of it as I would like. I am looking to buy an extended battery, but after researching them I have found prices and reviews to be all over the map. What brand / model has the best results? Thanks!"

So, superphone users -- which USB battery pack serves you best? Feel free to toss out Evo-specific solutions, but universal ones could help the masses. And it feels good to help the masses.