in-app purchase, how to purchase for third part

Hi Everyone,

my company developed an App for back pain. The app is designed for patients (end users) that can use it to do excercises to get some relief. Patients can purchase extra-exercises or services.

I want to explore the possibility that third parties (eg. Hospitals, Gyms, Assurances) can purchase the extra-contents on behalf of patients.

I know there is VPP but it is only for paid apps not for free apps with in-app purchase.

There is a way to give credit or voucher spendable only for my app?

any other suggestion?

I thank anyone who can help me

in-app purchase, how to purchase for third part
 
 
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