for watches or old phones discovery, I watch Mrmobile on youtube.
for audio wearables, there is a french guy named PP World on youtube as well which produces truly amazing reviews, both professional, tecnical while keeping it amusing and entertaining. He travels quite a lot and often does part of its reviews while traveling in the streets or in a park etc… and he keeps beautiful shots at the end of the video. He also is kind of crazy which makes it 10 times funnier.
In the US, LTT is a must watch, Linus Tech Tips, but also shortcircuit and techquickie are all great ways to watch tech-related stuff, they are great produced videos with a lot of different staff which all have their kind of expertise/ personality.
A more low-key youtuber, but an excellent one is Snazzy-Labs : he has some different concepts of videos, a personality I love and a way of thinking I mostly agree to. GO check him out.
