sorry for my bad english but i'm italian.
I have to release an app that will work on only a few devices. What should I do when the provisioning profile expires? Will the app continue to work or should I release it again with the updated profile?
thx all
Not sure what you're really asking, but here is a quick answer with some points that might help you.
Ad hoc provisioning profiles last for 1 year. After a year the certificate is invalid and the application won't work any more. At this point you will have to create a new certificate (usually just renew the certificate will work) and re-release built against the new certificate. This will mean that anyone using the application this way will have to remove the app from their device and install the new package you send them.
When you release an application on the app store the certificate is permanent, you don't have to renew anything and apple will deal with it itself.
If you archived it, all you need to do is create a new .ipa (by selecting "Share" in the organizer) and sign it using the new profile.
If you didn't archive it you need to build it again and you'll need to reselect the code signing identities in the project settings.
Either way you need to send a new build or a re-signed archive to your testers, the new profile alone won't work.
No the app will not work after the mobileprovision expiration date. You need to renew your mobile provision, build again and sign the app with new certificate and resent to users the new mobile provision file and the new app.
Edit: You can submit for an enterprise account an you will not have this issue again.