Despite the API being very easy for programmers to use, Mophun has not been very popular. The main reason for this seems to be the strict approval process - the compiled program can only be run under an emulator, and Synergenix must approve the program so it can be used on a mobile device. The approved program can only be run under one IMEI number. Only developers registered and approved by Synergix can use self-certification (and through the Synergenix server), and they are only allowed to have one IMEI number. The developer must sign a sales contract with Synergenix, which then shares and approves it for end-users, so the program can be shared. Such a process disallows free programs to be created for Mophun, and also discourages many developers from developing programs for Mophun.