From a user:
"It works perfectly with my Mac and iPad Pro using a usb c adapter, but with my iPhone and a lightning to USB adapter I get the message Arduino draws too much power."
The same user can use the adapter on his Mac and iPad Pro without issue, so it seems the iPhone is more agressive with the current limitation than a proper USB port. SInce it is a "lightning" port and strictly not USB, they might not follow the USB standard fully.
From a user:
"It works perfectly with my Mac and iPad Pro using a usb c adapter, but with my iPhone and a lightning to USB adapter I get the message Arduino draws too much power."
The same user can use the adapter on his Mac and iPad Pro without issue, so it seems the iPhone is more agressive with the current limitation than a proper USB port. SInce it is a "lightning" port and strictly not USB, they might not follow the USB standard fully.