Among the major mobile platforms, LiMo used to be the only player in the open source field. Nokia has moved in this direction after acquiring Symbian OS. Google has also followed this trend. The transition phase from a closed to an open architecture will be critical for the future success of the platform [5]. The shift, depicted in Figure 4, of this major player towards openness means that from a situation with mostly closed systems, we have moved to a situation with a small majority of devices running an open source system. Nevertheless, this shift does not indicate that other platforms will follow. Among the closed platforms, RIM is probably the only one that might go open source, since Microsoft and
Apple are strong advocates of proprietary software. So far, it is still hard to evaluate what impact open-source software might have on the current mobile application developments. The successful model that Apple established does not suffer from the proprietary software clauses. The other platforms hope that the open-source option could help them to better compete in the platform war.