The Pinephone supports convergence, but there is still a lot of work needed on the software side. The under-laying technology "Plasmashell" is able to run different view modes: the traditional desktop mode, the mobile mode and the smart tv mode (https://plasma-bigscreen.org/). The missing link is the possibility to switch the view at runtime.

Now while I think the feature is cool, I'm not sure how useful it is. I don't really see myself using it and would prefer in almost all the case using my thinkpad with a good processor and plenty of RAM. This might change with future versions of the Pinephone getting more powerful with the time. For the moment, I'm happy to have the convergence of the applications with Kirigami, so that I only need to develop them once and use a similar interface on both my phone and laptop. And having KDE Connect to share stuff between my phone and my laptop.