Micromax has revealed that the next phase that they are working on is 4G support and Windows based devices. Probably by end of 2013, you might see some of the Micromax devices supporting 4G and some running on WP8 OS.
Micromax had launched the canvas 4 yesterday and I believe that it did not go as well as they might have expected. Rahul Sharma, MMX Co-founder stated that they are waiting for the 4G services to be easily accessible. As of now there are limited 4G services in India. Micromax will launch 4G devices (handsets as well as dongles) once the ecosystem is ready.
A Windows Phone 8 powered handset from Micromax, would be interesting, and even more if they can make it more affordable for consumers. Well MMX is working on that and probably future phones and tablets with 4G / WP8 might get affordable.