App 2023 – present

Adventure Cache

Geocaching and exploration companion — hide caches, log finds, earn badges. Shipped to iOS and Android.

The River Marker Cache screen on an iPhone: a Cache Objective card for a traditional cache with one visit, item, hint and question, above a Next Move panel reading “Start with the active clue question, then head to the map.”, Seeker view, one active question and one hint, one visit and one item, and Open Directions and Check Weather buttons.

What it is

Adventure Cache is a companion app for geocachers, metal detectorists, and anyone looking for a reason to head outside: create geocaching adventures, hide caches, log finds, and earn badges. Caches, items, and adventures sit on a map with walking or driving directions, and detectorists get equipment profiles that tie their machine to the finds they log. It is live on Google Play and the App Store.

The rebuild

Adventure Cache began as a Xamarin.Forms app with separate Android and iOS projects. I rebuilt it as a single .NET MAUI project and kept its identity intact: the package identity, signing, offline field records, and sync queue all had to carry over. It was not a clean swap. Production rounds turned up Android startup and first-install database issues, then an iOS first-launch crash in App Store version 20.1, which version 20.2 fixed.

What changed afterward

Fresh installs, first launch, and the exact build the store delivers are now release gates of their own.

Read the engineering write-up on earlhayes.com