Thanks Jane! That was a really complete answer.

There are at least 2 encoding for Burmese: Unicode (recommended) and Zawgyi. Most local Burmese people use Zawgyi. You need to choose one of them, and both sender and receiver should have the same encoding to read the script correctly. It is still very challenging. Settings for computers (mac or windows), and for phones are all different. Here are some guides: http://www.bamalearnburmese.com/img/resource/Burmese_fonts_guide_JO_2017.pdf