What are some alternatives?
When comparing glitchi and CharMap, you can also consider the following products
generative.app - Transform your images into compelling algorithmic art
Bluegrams Screen Ruler - A lightweight and configurable ruler tool for Windows Desktop.
Pixus - Pixus is an AIR pixel ruler application, a handy tool for web and interface designers.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Glitch Wizard - Create trippy glitch photos and animated GIFs
Hyperspektiv - Psychedelic glitch fx