Truphone said customers they may encounter service problems with the current version of the Truphone application (version 3.0.2) if they install OS 3.1.
Truphone makes software for the iPhone which enables people to make telephone calls via the Internet rather than the cellular phone network. Such calls are usually substantially cheaper, particularly for International calls.
"We are aware of an issue and already have [an updated version of the Truphone app] with Apple for approval. We're working with Apple to ensure a speedy release of this update. In the meantime, if you are a frequent user of Truphone and wish to maintain an uninterrupted service, then we recommend that you do not upgrade to Apple iPhone OS 3.1 until the new Truphone version is available," said Truphone in a letter to subscribers.
We have not heard from other Internet phone app vendors but existing versions of other products might also have an issue with OS 3.1.
Not for the first time, it seems an update to the iPhone software has caused problems with iPhone apps.
