Moving an AIR app from paid to subscription model

Hi,

I've got an existing AIR app on iTunes and Google Play that I'm thinking of moving to a subscription model.

Has any here done that?

Was it simple/complex/needed a completely new relaunched product?

Are there any online tutorials about using a subscription model? I'd assumed I'd need to use an ANE but couldn't see one that supported such a thing.

Any tips would be greatly welcomed!

Cheers,

Minty