Stickers on photos is a fun idea but a bit of a stretch. If the end recipient is not using iOS 10 iMessage then they would just see the 'hat' and 'mustache' come through as sequential new message (unassociated with the photo).
I dont know of a way to learn what OS the recipient is using. i suppose they could send stickers pasted into the conversation in a place other than the next threaded spot.
Is this a stretch? Curious what other people think about costume stickers.
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