KMag
Screen magnifier tool
KMag is a small utility for Linux to magnify a part of the screen. KMag is very useful for people with visual disabilities and for those working in the fields of image analysis, web development etc.
KDE's screen magnifier tool. . You can use KMagnifier to magnify a part of the screen just as you would use a lens to magnify a newspaper fine-print or a photograph. This application is useful for a variety of people: from researchers to artists to web-designers to people with low vision. . This package is part of the KDE accessibility module.
How to install KMag in Ubuntu
If you are on a supported distro, you can install the application through software center by clicking the below link.
If the above link not working, run the below command in terminal to install kmag in Ubuntu
sudo apt install kmag