I really want to use a 2nd display since my “office” is never I the same place for more than a day. I want something very portable.
I am a Mac user so I’m tempted to use my iPad Pro, but there are some downsides to that.
I bought a very inexpensive display that worked fine for the most part but was dark and a bit awkward to pack up.
I’ve looked at the espresso displays online and they seem good, but expensive if they aren’t all they are cracked up to be.
I’ve used sidecar and like it for the most part. I do find that it sucks the iPad battery really quickly though. Not sure if that’s my iPad or if others have the same experience.
I’ve tried Duet Display awhile back, but found Luna Display to work better.
You can use it wirelessly, but peer-to-peer mode using a USB-C cable between my MBA and my iPad Pro works best, so the MBA is charging the iPad as it runs - plus response time is better.
I do a lot of graphics/comics work - so my portable second display is actually my main display - a Huion Kamvas 16" - it’s less than 1/2" thick, HD (there’s also 2.5K version) and it’s about 2.5 lbs.
I use this one, it’s 4K and you can run both data and power over a single thunderbolt cable from a Macbook (if you give it a dedicated power cable it will double the brightness), or it takes mini HDMI + power as well.