The situation is quite different in Japan where mobile hardware was much more developed, and major video game developers were much more invested in creating unique and high-quality content that's most obscure and unpreserved, let alone emulated, today. Those are the very different Galapagos mobile phones (like NTT DoCoMo i-mode, DeNa, RoID...). Some of these games got ported to the inferior Western hardware but these are in the tiny minority.