It is always refreshing when app developers acknowledge a problem and backpedal to a safer release even at the cost of much desired features. That’s what truphone does with this blog post.
They clearly state that: we are not happy with the way the app has been performing in background mode.. Their workaround was to release an update that removed the ability to receive calls when the app is in the background. You can, however, still work with other apps while in a call already in progress.
truphone is working on the background incoming call problem and will undoubtably release an update that restores the feature in the near future.