A:AnswerRead this:
"The iPhone 8 family was the first generation of Apple phones to support wireless charging, something which has been a mainstay in lists of potential iPhone features for the best part of a decade."
How to wirelessly charge your iPhone 7 >>>><https://www.techradar.com/how-to/how-to-wirelessly-charge-your-iphone-7>
A:AnswerHello, Kled. This charger is not compatible with the Galaxy A21 being that it is not a Qi compatible device. Thank you for asking this question. ^Kayla
A:AnswerHello! Unfortunately, you are not able to charge a tablet and a phone at the phone time using this wireless charger. Thank you for asking this question. ^Kayla
A:AnswerMy friend uses an iPhone in an Otterbox on my charger. It will work, but you may have to set the phone on its side to make the charger line up right.