The Covert Dock, by Genki, is roughly the size of a cell phone charger. Yet, it is capable of replacing the techincal functions of the first-party Nintendo Switch Dock. If portability or a reduced footprint are primary needs for you, this particular solution is the best around.
What it is
A small adapter that translates the audio and video from an original Switch (read: not Switch Lite) via HDMI. It is powered by USB-C and plugs into your wall outlet. Included in the box is the device, multiple outlet adapaters for worldwide support, and a USB-C cord.
$75 - via Genkithings.com
My one complaint is the time from “docking” to playing is about 3 seconds, quite consistently. Whereas the Nintendo first-party dock is comparitively lighting fast.
There are many third-party docks that have caught a wave of negative attention due to reports of Switch units bricking - meaning these other docks may effectively destroy your Switch. I cannot speak to this Genki unit as I have only had it for a week. There are no such reports that I have found as of publishing this post.