I rarely install apps because I don't want to navigate the uncertain security implications. On the few occasions that I do, however, a significant portion of those apps seem to be designed only for phone with larger screens. Essential parts of the display reside below the bottom edge of the iPhone SE screen. Some pages of some apps allow scrolling/panning, but not always. Sometimes, it seems that they assumed that no one would have a phone so small as to be unable to access the bottom portions of the content, so the content doesn't scroll, and I can't access the bottom parts.
For example, some parts of the Tim Hortons app for reward points allows you to redeem points for food/beverages, but some parts of the menu becomes inaccessible. Another example is an app to access a certain vendor's security camera; it requires that you create an account with the company, but I can only access the login fields -- not the links to create an account, which are below the bottom edge of the display. I don't know if I can use a friend's bigger phone to create an account, but even if I could, the controls for accessing the video are also way down, and would be inaccessible using my iPhone SE.
I tried using a pinch gesture to shrink the size of the content so that the content lower down on the page would fit on the screen. Resizing of the content doesn't seem to be possible.
The iPhone SE is not a rare phone. I can't be the only one butting against this problem. How do others deal with this?