X10III, SFOS 5.1.0.10
My phone language has always been EN (UK) .
Curiously, the Jolla Store displays some labels in French.
There’s “Jeux” and “Places de marché” instead of Games and Marketplaces.
The Jolla Weather app displays as “Météo” with description coming in French. And it still mentions FORECA as provider, btw
The SIM is French, I am located in France. Nevertheless, it shouldn’t matter. If I ever move to China, I’m toasted 
Any idea what’s causing it?
Store descriptions are based on the language set in https://account.jolla.com/. There was probably some reasoning behind it, but it really should be changed to just use the language set on the device.
Indeed, my account had Language set to French.
Nevertheless, its effects are very partial, only some of the items displayed in French. Now all set.
I’d expect the app to have a consistent policy, be it wrong
Looks like if it were driven by the server side of the store, and the app just displayed whatever it received. Speculating…