In this article, the developers of seven Language Massive Open Online Courses (LMOOCs), Icelandic Online (IOL, https://icelandiconline.com/), describe the technological and pedagogical principles that have contributed to the program's longevity. Development began in 2001 with a courseware system later upgraded to a multiplatform app. Over 80,000 users have completed one or more of the curated and pedagogically driven courses, which are monitored by a tracking system. The tracking system and follow-up surveys generate unique, large-scale empirical data enabling sustained engagement with participants' views and behaviors as they go through the courses, some of which are offered in three different delivery modes. Finally, further development projects based on the versatile IOL non-language specific, multiplatform system are presented, including Virtual Reality (VR) projects, courses in other languages, and L2 literacy courses for children. [For the complete volume, "CALL for Widening Participation: Short Papers from EUROCALL 2020 (28th, Online, August 20-21, 2020)," see ED610330.]