Installation app not from AppStore
Hello,
I'd like to install one app into my iPad (mini 4, wifi, cellular) and into my iPhone 8. I have the latest software in both devices. This app is not in AppStore, it is from my school (I trust this app). I can download it on my iPad but after intallation it is grey and I cannot open it. And when I download it on my iPhone - it is downloading, installing and then it disappear.
Any ideas? Thank you all very much, Vladislav
iPad mini 4 Wi-Fi, Cellular