XnView MP stands for Multi Platform = it is available for Windows, Linux and MacOS. It is a continuation of the older XnView Classic. In my opinion it is a great alternative to Windows photos app or any Linux image viewer that comes preinstalled. I even think it is an alternative to IrfanView. It is really fast and simple to use, supports more than 500 image formats, has built in folder browser, image converter, editor... AND MORE!
IrfanView - IrfanView ... one of the most popular viewers worldwide.
gpx.studio - View, create, edit and combine GPX files online to correct your activity data or design new awesome routes.
FastStone Image Viewer - FastStone Image Viewer is a fast, stable, user-friendly image browser, converter and editor.
GPX Editor - Load, modify and save your GPX 1.1 files.
JPEGView - JPEGView is a small and fast viewer/editor for JPEG, BMP, PNG, GIF and TIFF images.
GPS Track Editor - GPS Track Editor: Free Windows Application to Make GPS Tracks Better.