Many moons ago I remember being able to play online, and met some cool people. Grad/prof school got too busy so I didnt play as much and couldn't tell you the website. Theres got to be one out there
It's an older system but there are players on there. I was just about to get back into that myself. My dad plays on there quite often now that in person games can't happen.
There's a new online 42 game coming out but it's still in development.
im gonna have to check out some of these apps. Ive been playing the computer on https://www.ccdominoes.com/ for 15 years. theres an online multiplayer option but a $30 buy in is probly too much for most
There's a new, Aggie-backed, online 42 game available. This one has live video feed so you can play with your friends just like being in person. You can have private or public games. If you happen to be short a player or two, you can also play against the computer bot. www.shoot42.com or @Shoot42 on Facebook.