What is the ruling on profiting from an electronic application that relies on scientific questions and competitions, and offers prizes to contestants, with the presence of advertisements and paid subscriptions to unlock additional content?

Earning from this application is a form of ijarah (leasing/hiring), and for it to be valid, the wage (ujrah) and the benefit (manfa’ah) must be known. Therefore, if the advertisements are free from prohibited content, and the subscription amount and duration are known, and the purpose of paying the subscription is to benefit from the application itself, rather than the prizes, then there is no harm in the profit, and the prizes would be considered promotional gifts. However, if the purpose of paying the subscription is to obtain the prizes, then this is gambling (qimar) and forbidden maysir.