When downloading an Enterprise White Label build onto a device running iOS 9+ device from the web, you will run into the following alert:
After the app downloads to your device and completes the installation, please follow the below instructions.
STEP 1: Click Settings.
STEP 2: Click General.
STEP 3: Click Profile.
STEP 4: Click on the certificate for your company.
STEP 5: Click Trust.
The app can now be used on your device.