[rtkwe]

It does add a slight extra layer in that they have to both have a compromise for whatever chip is controlling your bank and a compromise for whatever phone is attached which is more difficult to pack into a small controller chip. Although I'm willing to be a lot of power bank controllers are similar across the market which narrows that difficulty.

[seanmcdirmid]

If your power bank is qi (MagSafe) to your phone, it will probably be fine given the lack of a wired connection.