Here is a list of all free databases for Network Location Services, plus their Client Apps and our rankings as far as I have found. Since this is a #wiki you can add yourself to the highscore lists if you want.
You can discuss this post here.
MozillaLocationService
Website, Map
Cell Data: 41.14 m * (public domain)
Wifi Data: 1280.99 m * (not free because of privacy concerns)
Bluetooth Data: 0.16 m * (license?)
Location App: µg UnifiedNlp (free: Apache 2) with Backend: online
Contribution App: Mozilla Stumbler (free: MPL2)
Fairphone Forum’s Top contributors: *
- #1282 @paulakreuzer (as user_15408851921) ( #36 in Austria)
@sam, @Lidwien, @Stefan, @Herve5, @mdione please add yourself as it’s hard to find someone else on the new leaderboard
old leaderboard
- 294 @sam (as ssam)
- 324 @paulakreuzer (as paulkreuzer)
- 919 @Lidwien (as Tux)
- 2276 @Stefan (as newluck77)
- ~2687 @Herve5
Open3gMap
Project seems dead
Cell Data: ?? (free: GPLv3, BSD)
Wifi Data: -----
Location App: -----
Contribution App: Sensorium (free: GPLv3)
Fairphone Forum’s Top contributors: no list
OpenbMap
Website, Map
Cell Data: 870 k * (free: CC-BY-SA 3.0, ODbL)
Wifi Data: 14 m * (free: CC-BY-SA 3.0, ODbL)
Location App: µg UnifiedNlp (free: Apache 2) with Backend: local or online
Contribution App: RadioBeacon (free: AGPLv3)
Fairphone Forum’s Top contributors: *
- 7 @sim6
- 26 @paulakreuzer
OpenCellID
Website
Cell Data: ?? m (free: CC-BY-SA 3.0)
Wifi Data: --------
Location App: µg UnifiedNlp (free: Apache 2) with Backend: local
Contribution Apps: list
Fairphone Forum’s Top contributors: no list yet
OpenWlanMap
App and Website has problem with secure https and only works with http.
Website, Map,
Cell Data: ------
Wifi Data: 31.96 m * (free: GNU FDL 1.3)
Location App: none
Contribution App: OpenWLANMap (free: GPLv2)
Fairphone Forum’s Top contributors: *
- #2 Fairphone @paulakreuzer (map)
currently not on the list:
As a team we rank #1! 
(to join enter “BFF423CCC64D” as Team Identifier in Preferences)
See also:
Wi-Fi positioning system on Wikipedia