Apple Business Manager is a private distribution method for apps provided by Apple.
Apps published through Apple Business Manager are maintained in Apple's App Store, but they are not publicly available, so you will not be able to find your company's app by searching for it.
Instead, in order for you to install your company's app, the administrator for your app will send you a personal installation link via email. This link is assigned to you and should not be shared.
Note: if you are updating your company's app from a prior version that was not managed via Apple Business Manager, you will need to delete the old app, then install the new app from Apple Business Manager, re-login, and re-download all content, so plan time appropriately for this migration.
You will only use your personal link on for installing the app the first time. After that (for example, if you want to install the app on a second device, or if you get a new device and want to install the app), please follow these instructions.
To install the app on your iPad or iPhone, open your email on that device and locate your personal installation link. Press the link, and the App Store will open and prompt you to enter your Apple ID password. This is the password that you use with your Apple ID account, the one that you normally use to get apps from the Apple App Store. (Note - if you are already logged in to the App Store, you may not get prompted for your password, and you may skip ahead to the next step.)
The prompt will look like this on iPhone (scroll down for iPad):
This is what the prompt will look like on iPad:
Once you enter your password, you will see a notification that you have redeemed your code and your app is now downloading.
Close the App Store app, locate your company's app on your device's dashboard, and launch the app.
If prompted, enter an app code.
Then, sign-in with your company email address and app-specific password (this sign-in step is only required at install), or use your company's single-sign-on system if prompted. Your app-specific password was most likely provided to you with your personal installation link for the app.
Upon successful sign-in you will be prompted to install updates (must have Wi-Fi for this).
Accept updates.
Your company's app is now ready for use! To ensure both the app and content are kept up-to-date, please make sure to launch your app while your device is connected to WiFi at least once a week, and turn on Automatic Updates from Apple's App Store.
To install the app on additional or new devices, please follow these instructions.