What are subscription applications?

I heard this term recently. What are subscription applications(for a mobile platform). Do开发者_如何学运维es this term fall under standard usage? Are there any examples of such a mobile application?

Thanks.

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In subscription application you pay for right to use software for some period of time. E.g. application could cost for example $5 per month and as long as you keep paying, you can use the application.

I think that this is rather common term. I don't know about mobile apps but one example subscription based web app would be Basecamp. Another example would be StackExchange.

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Subscriptions on iPhone can be facilitated using StoreKit.