Apps I've Made
My current iOS apps. I welcome feedback via Twitter at @Joe_Duffy.
Gathered
Gathered is an app that facilitates the viewing, recording, and sharing of over 25 sources of data available on iOS and iPadOS devices, from the GPS and accelerometer to the advertising identifier and the WiFi. Gathered is the perfect app to enable the recording of all the data required to calulcate position, acceleration, and ambient conditions of the device.
Nevis

Find and install applications found in DMGs and ZIPs.
Configurable to watch directories, ask before performing actions, moving used files to trash, and is completely free to try.
Four Squares
Four Squares for iOS and Apple Watch is a take on an classic electronic memory game. Four Squares stays true to the original, while adding a modern feel and feature set to the game. It supports the iPhone, iPad, and Apple Watch.
All of my apps are released in my company's name, Yetii Ltd.