New Users Can't Be Added to Custom Apps

I have a few custom apps created in Connect, but anytime new users are added to Connect they can't be added to the custom apps. This is the case for both apps on the company wall and apps in groups. When I add new members to the group they don't have access the custom app. I event try adding the user in the app settings under user but they still never get added.

The only work around I've found is to re-create the custom app again, and then all current users are added to the app. But because I had to delete the previous app, any records stored would then be lost. This also a pain to have to re-create the app whenever someone new joins the platform.

I'm sure I'm just missing a step to get new users into the apps but I can't figure out what I'm missing. Any help would be appreciated.