On https://apps.apple.com/us/app/apollo-for-reddit/id979274575
In-App Purchases
Apollo Ultra Monthly $ 4.99
Amazing Tip $10.00
Generous Tip $ 5.00
Nice Tip $ 0.99
Kind Tip $ 3.00
Godzilla Tip $19.99
They may have a separate subscription service that isn't using Apple's. Or it is possible that the page wasn't updated at some point. Those prices, however, are the prices and match the app.
[1] https://apolloapp.io/pro-ultra/