Open-Meteo is an open-source weather API and offers free access for non-commercial use
Openweather faq:
1,000 API calls per day are included for free.
Yr.no does not offer commercial service, but jolla would need to get a special agreement, from link you posted:
Bandwidth
Anything over 20 requests/second per application (total, not per client) requires special agreement.
with them to avoid getting their user-agent banned like default android:
https://api.met.no/weatherapi/locationforecast/2.0/documentation#AUTHENTICATION
Examples of banned User-Agents include:
okhttp
Dalvik
fhttp
Java
Or you would spend dev resources only to have the weather fixed only to get broken again