Hi! 2 years ago i created an app with display mode "black bars" for iPhone and iPad (iPhone4 resolution).
on iPhone4 it looks perfect, on iPad it just have had 2 black bars left and right of the portrait screen.

2 years later we have to do an update on the app. usually we select "fit inside and adjust window size" to make it suitable for iPhone4 AND iphone5/6.
but this mode does not work for iPad, because of its dimensions (we would have to change a lot of code for full iPad support).

Is there any hack or workaround to have the display mode "fit inside and adjust window size" for iPhones and display mode "Black bars" for iPads?
(btw iTunesConnect do not let me publish an app just for iPhone, if it was ever published in the past for iPad too)

thanks for your suggestions!