There have been several VNC clients for RISC OS, but my favourite has always been !Avanlanche. It always felt the most polished to me and it had lots of useful features like a fullscreen mode, scaling and lots of choices.
I am still running version 0.22, released December 2009, although there was a later release in 2013 which added the option to open connections from your hotlist when you started the program. The software still runs on my Titanium and happily accesses my 2020 MacBook Pro laptop.
So I was really pleased to see some new versions. In March, there were 3 bug fix releases and the latest version is now 0.26 (released April 2021). According to the changelog, these are all bug fix releases, (very welcome) and no new features. It runs really nicely on my RISC OS machines, and I can see no reason not to update to the latest version.
There are still some older version on the Internet, and the latest version is to be found on Github
We hope reviewing new releases of Avalanche will become a regular fixture!