NexusImage is an ultralight portable image viewer.
If you are in a pinch and need a down and dirty image viewer with no frills, NexusImage is an excellent example to get the job done. It offers the standard features, zoom, rotate, flip, copy, etc. All of which are available from the apps dropdown menu located top left.
NexusImage works well and keeps everything as simple as possible, making it a great choice for image viewing, and since it is a portable app, you can have it with you on the go.