HL:Exp Mobile is a team that will bring you the Half-Life Expantions to Mobile. That is Blue Shift and Opposing Force.
I am not sure if this will work at all. Nobody in the team owns a BlackBerry. We just made this at one point just to see how our game will perform on...
This APK comes with better graphics and utilization of OpenGL ES, options menu, 3rd map, and a few more minor things. The downside is it's much newer...
Alpha 20 may not have as many features as 21 but it is very stable. I advise everyone to try out both!