Publish app as hidden and share the deep link
If you want a simple way to make your app available to some users, but don’t need to strictly limit it only to those users, publish the app as hidden, and then share the link with people. Anyone who has the link will be able to acquire the app, and this works for customers on Windows Phone 8.x, and Windows 10.
This option is selected by choosing Hide this app in the Store in the Distribution and visibility section of the submission process.
Publish app as hidden and prevent acquisition – use promo codes to grant access
If you need to limit access to the app, publish the app so it cannot be acquired by any user, even with a direct link, and distribute promotional codes to specific users. Note that once a customer uses a promo code, they will always have access to that app in the future; you cannot remove access to the app.
This is one of the most effective options to manage a closed beta and works for customers running all supported OSs (Windows 8.x, Windows 10).
To use this option, select Hide this app and prevent acquisition in the “Distribution and visibility” section of the submission process.
Then, generate promo codes for the app and distribute them to the individuals that you want to grant access to.
Note: Promo codes will work after the first app submission is live, so it’s recommended that you not distribute the promo codes until the app displays ‘In the Store’ as the publishing status.