Yes, Googles does GPS+WiFi, and CGI if they're desperate, but you didn't really address my claim. Each of the three location methods, UTDOA, GPS, and WiFI are

Yes, Googles does GPS+WiFi, and CGI if they're desperate, but you didn't really address my claim. Each of the three location methods, UTDOA, GPS, and WiFI are good at different things. They can all get 50m accuracy or better--when they work. GPS is great outdoors and rural, but has problems with indoors and urban canyons because of sky view, attenuation and multipath. It also needs ephemeris data periodically (ie AGPS) and 5 sat fixes, which can mean 30s to first locate. Obviously WiFi is good if you can get it; it's like a street sign. UTDOA has 5s fix times and works wherever you have a cell signal, indoors or out, and also has the feature it doesn't depend on handset software; it's network based. So you really want all three, plus maybe other weaker methods like CGI, ECID, or CGITA for hybrid locations. They're all good in different cases. So carriers ARE using two of the three methods as you point out. But UTDOA is network based (towers), not handset, so it's expensive and carriers hated it. So much in fact, that they colluded to keep it out of the LTE standard [0] and avoid that expense and IP issues. Skyhook, already dealing with Google [1] was bought by TruePosition, which then vanished into Skyhook since UTDOA was out of the picture. I'm pretty sure there's no UTDOA left in deployment. So you have 2 out of three handset methods but you're lacking the third. Which means despite new FCC indoor 50m location rules[2], if you're dying indoors with no WiFi, you better not call 911 and expect a good location [3]. This was my point about business. We have the tech on the shelf to make 50m indoor reliably, we just won't. 0. https://finance.yahoo.com/news/trueposition-ericsson-settle-antitrust-litigation-130505755.html https://finance.yahoo.com/news/trueposition-ericsson-settle-... 1. https://searchengineland.com/skyhook-wireless-sues-google-you-lie-about-openness-50902 https://searchengineland.com/skyhook-wireless-sues-google-yo... 2. https://www.fcc.gov/document/proposes-new-indoor-requirements-and-revisions-existing-e911-rules https://www.fcc.gov/document/proposes-new-indoor-requirement... 3. https://www.iafc.org/on-scene/on-scene-article/concerns-remain-with-911-indoor-location-accuracy-implementation https://www.iafc.org/on-scene/on-scene-article/concerns-rema...