@darkpaw Thanks for your advice. I think I have assemble two apps into one as you advised.

Thanks for your reply. The reason I made camera app and controller app separately was to prevent users from selecting the role. To me, it seems more complicated. Additionally, my app needs 240 fps recording, which is supported only by iPhone, not by iPad. Hmm... You guys think that rather let user choose the role in a single app would be better? I may have to consider that option more seriously. Because I already finished developing two apps, integrating them into one app is another task to me...