[MichaelGG]

I think it can return valid data, like empty sets or fake data. So apps shouldn't crash at all.

[dspillett]

Code that assumes it is going to get data instead of allowing for an empty response (in a circumstance where this is technically possible in reality but so rare the developer didn't thing to allow/test for it) could cause misfunction.

[pwnna]

That sounds like a bug in the application.

While I'm not exactly certain on how Privacy Guard works (I have yet to examine that code base), if a phone returns [] for a list of contacts and the application crashes...