Auto renewable subscriptions without server

Inn app purchase programming guide says: "Server delivery is appropriate for subscriptions, services and co开发者_JAVA技巧ntent, because these products can be delivered as data without altering your application bundle."

My question is: Is this a must? Or I can implement auto-renewable subscriptions build in product, without any server.

Thank you, Horatiu

If you need to transfer new data to the client:

you must have a server

If you just unlock something, that is already within your data:

you don't need a server

see In-App Purchase Programming Guide - Built-in Product