One of out favorite things at events are the new geocaches released to the attendees and published to Geocaching.com later on. The trouble is that some geocaching apps (including the official Geocaching® Apps) won't work for geocaches which haven't been published. The solution used for GPSRs (load a GPX file with the caches) will work with some of the third-party apps. Below is a list of those tested as of March 31, 2016 with links to basic instructions for a few;

PLEASE NOTE that the Groundspeak Geocaching® Apps do not work.

• ZIP compatible Apps for Android:
• c:geo (Free) [instructions]
• CacheSense (Free Demo/$5.00 Full)
  (requires saving the file to a shared directory or DropBox authorization)
  
• GCDroid (Free/$4.99 Full) [instructions]
• ZIP & GPX compatible Apps for iOS:
• Cachly ($4.99) [instructions / YouTube]
  
• Geocaching with Geosphere ($7.99) [instructions / YouTube]
• GeoBucket (Free Ad-Supported/$3.99 In-App to remove ads)
• Looking4Cache Pro ($8.99, "Lite" does not load ZIP/GPX files) [instructions / YouTube]