Here some hints about spectators equipment that I will bring to the tournament.
General
On Open tournament days spectators are not mugged and stripped of any electronic device as for example on the Masters. But for any electronic device you bring you should be VERY COMFORTABLE that they will never ever beep. Things to verify for are that there are no low battery alarms and no other unusual event that would trigger a beep or sound. Last year the the spectators rules say that cameras can not be taken to the course. If a marshal would ever approach me regarding the video camera I would hand it over without objection. Also: If it was written that cameras may not be brought to the course OR ANYWHERE ON THE PREMISES I'd respect that & return it to the car.
Video camera
I put a video camera in my backpack also during tournament days. I never use it close to the course or on grandstands, but no one has objected when I have been using it restrictively on the driving range or on the putting green. They post the exact rules by the entrance.
Range finder
I bring a Bushnell range finder to check how far the pros actually hit it on the obvious driving holes. I go to a point where most balls land & shoot from the carry spot up to the tee. Pretty interesting. Especially on the Open courses where the ball sometimes bounce and roll forever. A stroke saver might do a similar job, but not as conclusive.
FM radio
One great thing about the last two Opens was the radio commentary broadcasted during the tournement. VERY good. They have really good commentarys and bring in people from the R&A and other organizations to spice it up. Highly recommended. They also sell small FM radio receivers on-site. But the quality of those are so-so. I personally use a mobile phone with a built -in FM radio & put it in quiet mode. Works very well.
Shoes
On both Opens I saw I found it wise to use golf shoes. Some of the spectator areas on the courses were quite steep and I saw more than one spectator slip and fall pretty badly. St Andrews may not be as steep as Royal Troon and Royal St Georges, but it is what I'd recomment.
Binoculars
In some cases it is nice to have binoculars. Especially when you sit far out on the fairway. With binoculars you'll have lot better idea about the ball flight and weather you should cover your head or not. The laser range finder can probably double as that. It has to be binoculars with a pretty small amplification. The high-amplification ones are rather useless for watching golf. You will lose the ball the moment it leaves the clubface.