Hi everyone. Can I devolop an applicaiton that can download the ring tone, store it in my phone and set it for specified phone number or phone number group programmatically?

There are totally three steps in this proscess.
The first is to download the ring tone, which I think is not a problem.
The second is to store it in the phone.
The Third is to set it for given number or number group.

Is it possible? Do all nokia platforms provide API to do it, such as series 60, 80?
Is there any obstacle I should overcome in teach step?

Any suggestion or advice is highly appreciated. Thanks a lot