35.3 Electrically operated instruments or mechanisms. All electrical or electronic devices or instruments are prohibited except for watches, compasses and equipment for the recording of sound or pictures, unless otherwise permitted or required by the Sailing Instructions.
I believe that under rule 35.3 a strong argument could be made against the use of a micro Tacktick sailing computer. But since it has been in wide spread use for a long time, I shall not be the one to start such a discussion. Having said that, I would like to suggest that any device that can do things beyond what a Micro Tacktic sailing computer can do, should be prohibited under rule 35.3.