Can I Advertise an External API in My Free App Without Violating Apple’s Guidelines?

Assume I have a mobile app that provides users with weather forecasts. The app is completely free, with no ads displayed. Separately, I offer an API that provides access to the underlying weather data for €10/month. This API is independent of the app and does not alter its functionality in any way. To avoid using Apple’s In-App Purchase system, users create an account on my website, purchase access to the API there, and receive an API key. Now, I want to advertise the API in the app. Ideally, I’d include a button that opens my website for users to learn more. However, I’m unsure if this complies with Apple’s guidelines. Apple’s App Review Guidelines state the following under 3.1.3(e) Goods and Services Outside of the App: > If your app enables people to purchase physical goods or services that will be consumed outside of the app, you must use purchase methods other than in-app purchase, such as Apple Pay or traditional credit card entry. While the API isn’t a physical good or service, it’s entirely consumed outside the app. Does this guideline apply to my case? I couldn’t find anything more specific in the guidelines. Has anyone encountered a similar situation or have insight into how Apple might interpret this? **EDIT** Imagine the app to show one use case for the data and acting as a marketing tool for the actual product (the API).