google suggests not use GL11 in android ,but days ago , i find a application using GL11 , it invoke glBindBuffer and glBufferData to use VBO. so how many other GL11 features we can use ?

Where does google suggest this?

I'm guessing you are on pretty uncharted territory since if Google suggests that you shouldn't use the GL11 functions just yet since they are not fully implemented and might break on some devices, which is a bit of a pain but if you are ready to ride through that fire then why not. I guess the best way is to find out by trying? Which is naturally horrible to blindly try out things.

But yeah, my general advice would be to stay away from them from a while if nobody gives you a good list and details on how and with what the new functions work. Personally I'm such a coward that I want to wait a bit more to be sure of full support and thumbs up from Google.