I would argue that adding an attachment to an email reply is still a second or third class experience on iOS. You have to figure out how to get your app contain

I would argue that adding an attachment to an email reply is still a second or third class experience on iOS. You have to figure out how to get your app containing the file to copy the file to the clipboard, which is extremely inconsistent and undiscoverable between different apps. The problem is even worse for non-technical users that struggle to distinguish between an undocumented long-press and an undocumented double tap (don't even get me started on the wording behind "share to... Clipboard"). I really can't wait for the day when they solve this problem.