It is federated, no single point of failure. Use any of the following:

Temple of sats http://ngdk7ocdzmz5kzsysa3om6du7ycj2evxp2f2olfkyq37htx3gllwp2yd.onion/

BitcoinVeneto http://mmhaqzuirth5rx7gl24d4773lknltjhik57k7ahec5iefktezv4b3uid.onion/

TheBigLake http://4t4jxmivv6uqej6xzx2jx3fxh75gtt65v3szjoqmc4ugdlhipzdat6yd.onion/

http://robodexarjwtfryec556cjdz3dfa7u47saek6lkftnkgshvgg2kcumqd.onion/ (works for me?)

This might be helpful:

I did see one question on the telegram group, asking if Robosats was down. It's coming up for me.

I have the app that I downloaded from Github and everything is working correctly.

I had problems with clearnet but on tor and on my node its working fine

Seems to be working fine for me

I'm not having any problems neither on mobile phone nor on laptop. I have a couple of orders placed for a few hours already with two different coordinators and I've tried placing a third one with a different coordinator and all seems to work just fine for me. I always use the dex (third link of yours).

Yes, it looks like it's down; the links aren't loading at all, except for learn.robosats.com.