When you install the Abacus app and try to open it, you may receive a popup message that says "Untrusted Enterprise Developer". This will occur specifically for franchises which need to use a specialised pre-release version of Abacus (not to be found on the App Store).
In order to open the app, you will need to trust the app.
Go to your iPad's Settings
2. Go to General > Device Management
3. Press Kinnov Pty Ltd
4. Trust Kinnov Pty Ltd
5. Launch Abacus from the Home screen