Would be grateful for some advice. For over a year my app developers have been struggling to get my app working correctly on my Galaxy S7. The issue seems to be that some aspect of the login process fails unless I use an active vpn connection. This happens with both Facebook login and regular login. With the vpn on it all works ad it should. We see the same behaviour on 2 S7 Edge devices. It doesn't seem to be as simple as just having something blocked here in Dubai as with an emulator on my laptop the app appears to work. What could cause this very strange problem? We've been trying to solve it for a year. I can't launch the app until we fix it.
Android Nougat adds a feature whereby Android for Work apps can declare in their security configuration that the app can only work when connected to a VPN, for security reasons. There's a quick description of the feature (amongst other Nougat features) in this Ars Technica article. This page on the Android Developers website describes how the app developer can control the feature, but the description is very technical and a bit impenetrable.
The restrictions added inside the app interact with the Device Administrator app (such as AirWatch), so that your IT department can set a security policy that enables or disables the restrictions (just like any restrictions on password length).