Different human languages look different from other human languages. To use a term from the computer industry, each human language has its own “look and feel”. European English speakers can easily recognise a phrase such as “Comment allez-vous?” as being written in French while the phrase “¿Habla usted español?” is written in Spanish. Each language has its own letter frequencies, word frequencies and other identifiers. This paper describes key identifiers in MXit lingo as found in Dr Math conversations. MXit is a mobile instant messaging system which originated in South Africa and is expanding to other countries. Dr Math is a mobile tutoring system which uses MXit as a communication protocol. Primary and secondary school pupils can receive help with the mathematics homework using the Dr Math tutoring system. The pupils use MXit on their cell phones and the tutors use traditional Internet workstations. After exploring how MXit lingo is written, this paper will briefly explore why MXit lingo is written the way it is. By identifying and describing the orthographic conventions visible in the spelling of MXit lingo, although with some theoretical support, insight into the purposeful and functional nature of written, mobile communication will be revealed. In highlighting spelling that is influenced by Black South African English, an attempt will be made to contribute to the empirical development of a field of study that explores the construction of words used in South African mobile communication. Keywords: MXit, Math, letters, writing, orthography Disciplines: Linguistics, mathematics, information technology