“One of the most common reasons? Typing was just too hard.In Cambodia’s case, there has never been an easy way to type in Khmer. While Khmer Unicode was standardized fairly early, between 2006 and 2008, the keyboard itself lagged behind. The developers of the first Khmer computer keyboard had to accommodate the language’s 74 characters, the most of any script in the world. ”

Source : Fifty percent of Facebook Messenger’s total voice traffic comes from Cambodia. Here’s why – Rest of World