Check to see if your users have granted or denied permissions for common permission groups on iOS and Android.
Additionally, you can request permissions with a simple cross-platform async/awaitified API.
The PayPal Permissions SDK provides the following:
GetPermissions API Operation: Use the GetPermissons API operation to obtain the permissions associated with an access token.
RequestPermissions API Operation: Use the RequestPermissions API operation to request permissions to execute API operations...
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Owin Framework authorization middleware that checks if the identity making the request has permission to do so and returns a 403 response if it does not
A .NET library you can use to perform permissions based authorization. It allows you to administer the permissions as well as assert a member's authorization for a particular action, inheriting group permissions, and defaulting to deny anything not explicitly given.