Google voice number instead of a cell phone for 10 year old-am I missing anything?

My soon to be 10 year old has been asking for a phone for a while because most of his friends have one. My husband and I aren’t ready for him to have a phone yet, but we are willing to comprise. We are thinking of a Google Voice phone number which he can have on his iPad, so that’s he able to call and text with his friends. Im trying to think this through first though and I’m not super familiar with Google voice-am I missing anything with this idea?