Powermat is readying a pair of new wireless phone chargers to modernize its lineup. A sighting at Best Buy has shown charging add-ons for both Apple's iPhone 4 and HTC's Evo 4G. The brief Engadget tip didn't provide many details, but the iPhone 4 would continue the pattern of using a special charging case while the Evo 4G appears to just require a special battery cover.
