If you are an existing ChatGPT user, please log in with the same authentication method (username and password, Google, Microsoft, or Apple). When you're ready to subscribe to ChatGPT Plus, there are two ways to do so:
Go to chat.openai.com, click your name on the lower left corner of the screen, and then set it up via My Plan.
Or, via the iOS app. Tap the three dots which are located on the top right corner, go to Settings, go to Subscription.
For new ChatGPT subscribers:
If you've downloaded the iOS app from the App Store but find the subscribe button grayed-out (light purple), this indicates that Apple is still in the process of activating the subscription feature. The message above the button will read, "In-app purchases are currently unavailable. Please try again later". This activation may take up to 48 hours. We appreciate your patience during this time.