I am of two minds about a gyroscope in a cell phone. Since I am not a pilot (not to mention possible technical issues) I don't see a real world use for it right now. Still there might be something developed that would interest me, just not sure what it is. I am a serious astronomer and find Google Sky very useful, but do notice the lag; I just do not notice it enough to worry about it. As Krusty the Klown says "It's not just good, its good enough."
Bottom line is right now a gyro in a cell phone seems like an answer in search of a question; something that may change in time.