Question

I cache some downloaded information in the NSLibraryDirectory in an App. However after a recent update the users report having problems accessing the previously downloaded content in the Library directory.

Which directories are safe to cache information over new app versions? Is there any Apple documentation on this? I couldn’t find any…

thanks a lot,
e.

Answer 1

from Apple Application Programming Guide:

Files Saved During Application Updates
When a user downloads an application
update, iTunes installs the update in
a new application directory. It then
moves the user’s data files from the
old installation over to the new
application directory before deleting
the old installation. Files in the
following directories are guaranteed
to be preserved during the update
process:

<Application_Home>/Documents
<Application_Home>/Library 

Although files in other user
directories may also be moved over,
you should not rely on them being
present after an update.