How does Google Maps collect traffic data?

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Tags

1. #authorities
2. #local
3. #google
4. #traffic
5. #people
6. #including
7. #smartphones
8. #sources
9. #devices
10. #certain
11. #android
12. #iphone
13. #sensors
14. #anonymized
15. #sourced
16. #webos
17. #crowd
18. #using
19. #excluding
20. #highway
21. #fleets