It mainly has to do with the payment system . On browser, Udemy uses their own payment system, but on mobile apps they use 3rd party payment system. For example, on Android app they use Google pay for payments.
Read moreHow do I change price on Udemy?
If you opted into Udemy’s Deals program (check at https://www.udemy.com/user/edit-promotional-agreements/) then you’ve given them permission to adjust your list price.
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