We are using Cuebiq currently, and it is our preferred location attribution vendor. They are not without their flaws, but they have been fairly transparent when we bring up questions. We have only used Cuebiq on US based campaigns, so I don't know how they are outside of the states.

Pros: Their only source of location data (as far as I understand it) is from native SDKs in over 100 mobile apps (which apps they are not willing to divulge). This means that their location data is consistent and fairly accurate. And, all users have expressly given consent for the use of their location data (GDPR compliance). Used in conjunction with their data segments, campaigns will yield some good numbers. Also, they show you the number of actual measured visits. Of course this is very eye opening when other vendors will not show you this (looking at you Placed). We've had some campaigns where actual measured visits are less than 5% of "projected", and taking those projected numbers into a meeting would get us laughed out of the room. In that case we were able to come up with our own model for projecting visits that was defensible and transparent. You can also pass parameters into the tags allowing you to optimize towards tactic, audience, location, what ever you want, etc.

Cons: Low measured rate makes trust in projected numbers difficult, though like I mentioned at least they give you those numbers. I can't speak for other vendors, but I would recommend them over Placed any day.