Solaris Sky Calendar - An astronomy calendar right in your pocket
digiKam - Professional Photo Management with the Power of Open Source
Lumy - Helps you track photographic times
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
Sundial App - Sun & Moon times and alerts for iPhone, iPad, & Apple Watch
Photos on macOS - Photos keeps your images organized and accessible. Rediscover favorite shots with Memories. Access them on your devices with iCloud Photos.