Apple's MagSafe Battery Pack designed for the iPhone 12 models has a unique feature that's long been rumored but never introduced in an Apple product -- reverse wireless charging.
When attached to an iPhone that's charging via Lightning, the iPhone can deliver power to the MagSafe Battery Pack, which is the first instance of an iPhone being able to route power to an accessory device.
We've long heard rumors of reverse wireless charging capabilities for the iPhone, a feature that's been talked about as a possibility for both the iPhone 11 and the iPhone 12. Apple hasn't actually implemented reverse wireless charging until now, and the way that it works with the MagSafe Battery Pack is limited in scope.
With the MagSafe Battery Pack, the iPhone has to be plugged in for the charging feature to work, but it's certainly a step in the right direction and hints at more expansive reverse wireless charging capabilities in the future. Given the MagSafe Battery Pack's reverse wireless charging feature, it seems technically possible that an iPhone 12 could deliver power to the AirPods or AirPods Pro, but Apple has not yet implemented this feature.
Apple has suggested that MagSafe Battery Pack users might want to use the iPhone passthrough charging feature when the iPhone is connected to a power source like wired CarPlay and is able to charge both accessories.
