My Airmail Pro subscription of $9.99/year renewed in January. On a review of my subscriptions yesterday, I noticed that my next renewal is $39.99/year. The other plans are $3.99/week and $7.99/month. I don’t know when this 300% increase takes effect so check your subs.
That said, I will probably renew as it is still the best iOS mail app I have found.
Don’t they need to present you with that increase so you can authorize it again? I didn’t think that much of a percentage jump could automatically renew. If yo want to continue using the app you’re stuck with it either way, of course.
If the increase does not exceed approximately USD $5 and 50% of the subscription price, or USD $50 and 50% for annual subscriptions, and where permitted by law, developers may change the price without interrupting service.