If you have an audience that is interested in Apple products and you can deliver a significant amount of high-quality traffic then the Apple Services performance partners program is worth considering.
With this program, you will be able to promote a number of Apple products including Apple Music which gives access to more than 60 Million songs, Apple Books which provides access to books and audiobooks, Apple News+ for all your news subscriptions, and Apple TV+ for streaming TV including Apple original content.
You will need to apply to be accepted into the program and if you are accepted you can start referring traffic to Apple products via the Partnerize network. Acceptance into this program is not automatic but if you are accepted the rewards can be significant.