Which app are you using?
The one I've installed on my iPad is an iPhone app, and it works without problems.
This is the one I'm using:
View attachment 68193
It's an iPhone only app. I've logged in today, and loaded a few pictures to the app. No need to purchase anything.
Are you using the same one?
Don't think that's the one I have on my iPad, I'll download that to my iPhone and try it.
Thanks.