I’ve noticed one thing in DC-iOS and another one in DC-Desktop that could be improved.
DC-Desktop:
The UI can be a bit confusing for new users. There’s a paste button at the bottom and a gear button in the bottom right corner of the camera view. The paste button allows you to insert a code from the clipboard, and the gear icon lets you choose whether to paste a code from the clipboard or load the QR code as an image.
I think it would be better to remove the gear button. Most people perceive it as a settings icon. Clicking the paste button could open the same context menu as the current gear button. It might be helpful to add a chevron to the paste button, similar to the ones in GitHub, to indicate the context menu.
DC-iOS:
Unlike the other versions, this one lacks the option to load the QR code as an image.