Certification of Aircraft Phone/Tablet Mounts/Holders I would like to know, whether it is required for such items to be certified for application on genaral and/or commercial aircraft:

https://www.rammount.com/part/RAM-B-166-MP1U

https://mgfproducts.com/products/sport-mount-flex-suction?variant=10434660040819

In what countries is it necessary?
Is it compulsory or not for them to be certified?

I would be gratuful for any help!)
For general aviation no certification is required, neither is certification required for at least some commercial operations like flight training, at least for the regulatory bodies I'm familiar with (FAA and EASA). I've seen Ram and Garmin mounts being used on some smaller passenger and cargo operations as well, usually GPS and tablets in older prop airplanes like the DC3, Beechcraft twins and the like. 

As for carrier airline operations I am not sure.