i figured out how to send the picture and put a message or write on the picture. :o).
and for +Jonas Jerner
Allo doesn't require someone to have a google account and you can group chat in it and use the assistant, send pictures which you can write on or type on etc. also you can message either android or ios. the other person doesn't have to download it to answer if they don't want to. they have the option to just answer it or download it and answer it.