I would buy this app but will not subscribe – Todo Math Review

I think this app is one of the best math apps I've tested so far. I have three kids. Currently my oldest is ready for this app. I'd be willing to pay for this app but they changed it to a subscription model. They charge $35 for a 1 year subscription and $60 for a 2 year subscription. Meaning that if I wanted to let all three of my children use this app for when they are ready for it I potentially would be paying $180-$240 for all my kids in the next 6-8 years when they are ready to use this app. It's a good app that encompasses a lot of different math concepts. But it's not $180-$240 good. I can pay for different apps that get all the concepts and I can keep those apps for a fraction of the cost. I contacted them a week ago asking if they have any plans to go back to previous version where I've seen reviews saying they paid $20 for the app and did not receive a response.
Review by Wahleeanna on Todo Math.