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We're building an app for a client that is providing emergency services to employees of businesses that have insurance policies with our client (it's a value added service they're providing to their clients). The issue is, they only want the employees of their clients to be able to register on the app. At the moment, once the user downloads the app and enters their details our client gets a notification which allows them to approve or deny the user access to the app. (This is working fine on the Google Play Store). I'd like to know whether this model is support by the Apple App Store and if so which program should we enroll in? Our current thoughts are to have our client create a business manager account use the VPP to send vouchers to specific users, but we're not sure if there is a better way forward.