With CalyxOS, it replaces Google Maps with Mapbox within apps, one example is with Uber as shown over here (I am sharing the part where he talks about Mapbox):
Is this the same with iodeOS? At least it replaces Google Maps integration within apps with something else and it works out of the box like CalyxOS?
Yes, Google Maps are replaced by Mapbox in iodéOS. This is part of MicroG, where the two implementations exist: we made the choice of the Mapbox one.
Interesting, thank you 
My signal messenger seems to struggle with this replacement. I cannot send locations, it appears fine in the preview but then there is no map when I eventually send it off.
Do you have the same issue?
WhatsApp btw works fine