RIM are no longer supporting BIS on other platforms, which is why it's not available on android, and it has limited functionality on windows mobile (it may not be available for Win 7). Bear in mind when RIM had introduced this idea Android did not exist and they have made no move to expand it since the introduction. However there has been talk of creating a Blackberry OS application for other platforms that would run BIS (but the last I heard of that was more than a year ago) it would appear the idea is dead and BIS will only be for Blackberry's and those handsets they initially supported. Pure speculation on my part as they have not made any official announcement regarding this.