did the whole thing on my computer and it was well buggy. Kept replacing the existing photos I'd uploaded with the latest one I uploaded. Only managed 3 pics then it wouldn't let me do more. Bit annoying as pics are kinda key when selling something...
Sometimes I post one pic with like a '.' As the text and then if you post the next pic with the exact same text it groups it into the previous post. I'm unsure if it works with anything other than a full stop as I haven't tried.
If someone posts between your posts it won't work though.
I find I cant upload 5 pics when using my phone but works on the computer.