Paypal express checkout vs REST api?

Question

I have been searching all this while and couldn't really find any documentation which tell, why one should use express checkout or REST api?

Can someone please tell me the difference between these?

I need to implement online payment gateway for user to purchase a plan and then continue using the application online (more like a service).

With express checkout I found 'Physical' and 'Digital' item categories. I am not providing any goods to the users ( no online store in my app ).

What should I choose? Please help.

Answer 1

PayPal REST API is something new (especially on mobile) to replace the classic APIs in the very future, but apparently it's still too early to see the classic APIs as obsolete.

It's quite equivalent whether you chose REST APIs or Classic APIs, either of them would fullfill your business needs (in this case, a recurring payment / subscription on your app), so specifically in the classic API world, you may refer to "Recurring Payments with Express Checkout", while in the REST API world, you may check with "Billing Plans" and "Billing Agreements"

I would recommend you to read this question for a further comparision between PayPal REST APIs and Classic APIs