It is need to know, though the only desktop that I have access to that still runs opera is already running the good old one, but it is also a old mini laptop As for the phone use I mentioned, I have a windows phone, and opera is just amazing for that purpose. I also use the android version of opera for my tablet, but thats slightly different.
Additional reading:
- https://en.wikipedia.org/wiki/Presto_%28layout_engine%29
- https://en.wikipedia.org/wiki/Opera_Mobile
- https://en.wikipedia.org/wiki/Opera_Mini