I have an s6, I can send a picture, I can send some text, but they will not be combined into the same message for some reason. It's maybe happened twice super randomly and I just can't figure it out. Any one?
i think that change happened a while back either when they tried to fix the multimedia bug or when the new advanced messaging became available.
I too remember on other phones being able to add a pic and then text.. but now as soon as you select a pic and hit OK it automatically sends the pic. So your not alone in wanting that feature back.
open gallery, open the picture you want to send, tap on share (if you can't see the share button tap once on the picture), select the messages app, then write anything you want under the picture, then chose recipient, then tap on send