I've been migrating my photos from iPhoto to Aperture to Photos and had sometimes to adjust for the location, either it was not present in the original file, or it was not precise enough (and sometimes wrong by several kms). So my Photo map view is up to date. 

However, when I look at the location inside Peakto Map view, I sometimes find a different location for the same photo.

Typically a photo with its (wrong) EXIF location, not taking into account that it had been updated in Photos before.  

So my question is how to handle it. 

What is the default Peakto behavior, does it take the exif data or the Photos.app data ?

Is it a bug, normally it should be handled correctly, but I messed with the import process ? For exemple updating the location info in Photos after it was imported in Peakto ?   

If I change it now in one app, is it further synchronized in the other ?

I coud consider writing a small program to check if the data are correct in Peakto then update it if not, but I don't want it yo be erase by future Peakto versions. I understand Peakto could read xmp sidecars but I want to be sure they have priority on the exif info.

Thanks for the answer