Great analysis which is the first I've seen to come up with a reasonable explanation for the existence of this file. Caching this data is a logical method by which to speed up location lookups.
However, there's no reason why this data should not be stored by default under the OS's "Data Protection" encryption as email is by default on devices where a passcode is set:
However, there's no reason why this data should not be stored by default under the OS's "Data Protection" encryption as email is by default on devices where a passcode is set:
http://support.apple.com/kb/HT4175