GSAK (Geocaching Swiss Army Knife) - GSAK is the all in one Geocaching and waypoint management tool.
Google ARCore - Google Augmented Reality SDK
Geocaching - Geocaching is the premier app for locating geocaches. This app is available for both the Android and iOS platforms, and it makes locating these popular hidden treasures easy and fun.
8th Wall - Cross-Platform Mobile AR
c:geo - c:geo is simple yet powerful unofficial geocaching client for Android devices.
Wikitude SDK - Wikitude’s all-in-one AR SDK combines 3D tracking technology (SLAM), image recognition and tracking, as well as geo-location for apps.