The subscription system is a good way to generate income for developers, but it is somewhat unfriendly to users. Users will always forget the products they have subscribed to before, and users will feel that they have lost a lot of money in vain. Sometimes, some users will report you due to automatic subscription issues, resulting in the payment account being banned. I hope there will be revenue models other than advertising, subscriptions, alliances, and donations. Every product needs to find a good revenue model.
