The iPad on Beamer

I have gained this adapter, so that I can use my iPad in the classroom. Thus, I can save myself the notebook.
The only negative point I have found is the connection to the iPad. This is just too shaky. One has to be extremely careful that you the iPad not very moved otherwise slip the plug from the iPad and you lose the connection to the projector. This can be very stressful. But if you have times outside the rotation, it is ok.
But there's "only" 4 stars! Perhaps other vendors are there a little better.