Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
You are, I think, asking about a situation where one device (the iPad) is trying to share files upon the Internet (in Pinterest's site), and also you wish to use Pinterest to access photos on another device (- an Apple Air laptop?) .... and are failing to get both desired tasks done.
In such cases, privileges of file access (read, write, list, for instance) are often crucial to the case. Saying "it cannot be done because iOS 9', is perhaps a cop-out; With the right network permissions, the operation should be able to proceed, even if not as smoothly nor in quite the same manner as before.
One aspect of network permissions that is quite important in such a case is:
- Do you have full access permission from the Internet site (e.g. Pinterest) to do the file transactions? that is, are you logged in to the web site, on the particular device (or, devices) that the transaction is taking place on or the devices that it will affect ?
In short, being fully logged-in to the various sites is important to getting this process working.