I'm trying to get an Ubuntu laptop functional for a visually impaired friend. Her impairment is such that a screen magnifier would solve the issue. I've tried out Kmag (as its the only hit when searching the software center for "magnifier"), but it seems odd the Ubuntu lacks a default. So I'm assuming I'm missing something obvious.
Ubuntu – Default screen magnifier
Unity (until Ubuntu 17.04)
CompizConfig Settings Manager
To use magnifier in Ubuntu, you can do so by using CompizConfig Settings Manager. If you don't have it installed, you can do so from the Ubuntu Software Center.
Or, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below.
You can also use Synaptic Package Manager
Once you invoke the program, look under Accessibility for magnifier, and click on it to configure it.
Or you can try Virtual Magnifying Glass 3.5