I had an original Atari Lynx I back in the days. I was thrilled as kid with playing almost Amiga quality games on a handheld. It has 6 AA batteries which didn’t give you a lot of playtime. I mostly played California Games on it. It was amazing for that era. You have to remember it was competing with the Nintendo GameBoy which has no color.
I added a Lynx II with these mods to my collection:
McWill
Zener Diode
Mosfet IC
Games:
California Games
Accessories:
LynxSD for Atari Lynx
Information:
https://en.wikipedia.org/wiki/Atari_Lynx
http://www.old-computers.com/museum/computer.asp?st=2&c=1241