I sometimes think about a possible app idea that manages your monthly subscription payments (like Apple Pay but only deals with monthly subscription fees) which

I sometimes think about a possible app idea that manages your monthly subscription payments (like Apple Pay but only deals with monthly subscription fees) which allows all the payments to set the same deadline all at once. Not only that, my idea was to have standardized contract and ToS that users find easy to navigate and understand that also allows subscription and cancellation through the app (generate some sort of token to allow you to receive the service immediately), not through the company website you pay for. I believe Apple already does this to an extent in their app store, but I have not seen any app that works for all platforms smoothly. Of course you need to have the subscription service companies to be on board, and maybe that is why it does not exist.