ChatGPT Plus has a listed price of $20, but the actual cost you pay can vary...

https://wiki-planet.win/index.php/Are_Modified_Android_Apps_Real_ChatGPT_Plus_Access%3F

ChatGPT Plus has a listed price of $20, but the actual cost you pay can vary from about $13 to $27. This difference happens because of taxes like VAT or GST and extra fees added by app stores on iOS and Android