The Galaxy S6 has wireless charging. The HTC One M9 does not. There's a pretty good reason for this: metal interferes with the current methods for wireless charging, so you can't have your fancy metal phone and charge it (wirelessly) too. Engineers at Qualcomm have a solution to that, at least according to the company's latest press release. It's a newly-announced functionality of the existing Rezence wireless power standard, which is different from Qi and PMA.

According to Qualcomm, the Rezence/WiPower standard operates at a frequency that's more forgiving of extra material in between the contact and the receiver, including everything from metal to empty space. It does operate on a magnetic resonance principle, so it's not clear if ferrous metals and alloys can play along - if not, then steel and steel alloys would be out, though aluminum and titanium phones would still be acceptable.

Samsung's Electro-Mechanics subsidiary is a member of WiPower along with Qualcomm, and the company has shown willingness to incorporate multiple wireless power solutions into a single product before (see the Galaxy S6 and S6 Edge). Then again, Rezence is a standard of the Alliance for Wireless Power (A4WP), which announced its intention to merge with PMA earlier this year. Who knows what standards and features will make it into final products after the mess is sorted out.

PRESS RELEASE