Family sharing is one of the most advanced iOS 8 features. While the feature can bring harmony to the digital life of your family, at times, you feel it annoying because of issues of downloading or updating apps. There are some reports of errors when free applications are downloaded or uploaded for a particular group of people -say, family. The problem persists as such apps aren't compatible with Family Sharing option.
Though there is no concrete solution available till date (nor has Apple come up with), we recommend you a little trick that might work to overcome this problem.
If you cannot update an app, get rid of it completely. In other words, remove the app for what you are having a problem with updating. While we just spoke about “updating problem,” for those looking for “downloading” problem, read it further.
Step #1. The first thing you must do is SIGN OUT of your iTunes and Apple Store account. Remember, do not sign out of iCloud, as it's not needed.
Step #2. Launch the App Store app on your iDevice.
Step #3. Search for the app you were having trouble for.
Step #4. Tap the cloud icon or “Get” whichever you see there.
Step #5. Tap on “Use Existing Apple ID.” Now, you'll be asked to sign into your iTunes account. Carry on and sign in.
Step #6. The download shall start, and you see no error!
Remember, this is merely a quick fix and not the permanent solution. This fix shall allow you updating or downloading the application that was giving you an error.
Why does it happen?
We don't have concrete evidence, but it seems that some application developers don't make their free applications compatible with Family Sharing feature. So, even if they are free apps, anybody has already downloaded the app, others find it difficult to download or update the same.
Bear in mind that this quick fix described above is said to work only for free applications on the app store. You cannot download the app if it is paid and not compatible with Family Sharing -no matter whether someone from your family group has bought it. You'll have to spend some bucks to get it!
Hope this helps.