The advertised ChatGPT Plus price is $20 per month, but the actual cost often...

https://www.slideserve.com/aaron_ward92/why-does-chatgpt-plus-cost-more-on-android-than-on-the-web

The advertised ChatGPT Plus price is $20 per month, but the actual cost often ranges from $13 to $27 depending on where you buy it. This variation is mainly due to taxes like VAT or GST and extra fees added by app stores on iOS and Android