Wireless charging has always been a limited use technology. It's pretty cool because we can simply set our device on a surface and it'll charge without any wire attached, however, it's limited because it is impossible to use the phone while it charges is pretty difficult, impossible really, when we pick up the phone from its charging pad, it stops charging.
oppo developed a new Wireless Air Charging technology to solve that problem. As a feature on their rollable concept phone, OPPO's idea for Wireless Air Charging is by holding the device about 10cm off a charging mat and have it still charge with a 7.5W of power.
It is a bit more convenient than normal wireless charging but not perfect yet, however it is a start. With this idea, we could hold the phone and use it, possibly even resting your hands on a mat that'll keep charging it through the air.
Since this is a technology in a concept phone, it won't be available any time soon. But let's hope for a bigger breakthrough