Intetesring Discovery about GPS apps

Maybe you already figured this out. I can't believe I wanted like 18 months to test this. I use Sanoodi for when I go running. It's a decent app. When I go for a long run (4+ hours), I can get a little concerned about battery life. Today I confirmed that both Sanoodi and Latitude work even when cell service is turned off. Sanoodi is not that surprising. I'm surprised that Google Maps, however, still painted the map even with cell service turned off. Maybe something was cached. Don't know. Thought I'd pass this along. You don't need cell service turned on to use your GPS app. This should save battery life.

Storm 1 still in effect as Incredible is on back order :(

you must have had it cached because there's no way your phone pulled your map data through a gps connection.

Originally Posted by sonicxtacy02

you must have had it cached because there's no way your phone pulled your map data through a gps connection.

Google maps caches a lot of data, and also has a very generic base map preloaded. I have used this trick when overseas, to have a very basic navigation tool without paying the $5/mb for roaming data.

Getting the GPS fix itself does not require cell service. If the app had previously downloaded a map that covers the location, you are in business.

Originally Posted by BSG75

Maybe you already figured this out. I can't believe I wanted like 18 months to test this. I use Sanoodi for when I go running. It's a decent app. When I go for a long run (4+ hours), I can get a little concerned about battery life. Today I confirmed that both Sanoodi and Latitude work even when cell service is turned off. Sanoodi is not that surprising. I'm surprised that Google Maps, however, still painted the map even with cell service turned off. Maybe something was cached. Don't know. Thought I'd pass this along. You don't need cell service turned on to use your GPS app. This should save battery life.

Storm 1 still in effect as Incredible is on back order :(

i too run and bike with my S1 and gps on.. i use gpslogger (free).. but neat too.. even gives me a path view where i can see the path i ran and even come back to it if i got lost.

now im overseas using a local sim card with no data package.. i still run fine with gps as its a separate system and works great too. most often you wont have to worry about gps apps since of course they use satellites to help locate your position.

now only thing thats left for me to do is to run past the 1hr mark hehe. good job on the 4+ hrs!

google maps and 3rd party GPS apps use zero data to run! It works off of autonomous GPS while BB maps and VZ nav are the ONLY apps to run off "assisted" GPS or A-GPS which uses network data to triangulate position indoors, outdoors and whereever theres a network signal

Originally Posted by RicanMedic78

google maps and 3rd party GPS apps use zero data to run! It works off of autonomous GPS while BB maps and VZ nav are the ONLY apps to run off "assisted" GPS or A-GPS which uses network data to triangulate position indoors, outdoors and whereever theres a network signal

Huh? Google Maps uses A-gps and *lots* of data to operate, although A-gps is a joke most of places I go since it's only accurate to 1km if i'm lucky. BB maps is a little better about the data (the maps are more compressed) but isn't even as good about A-gps as google maps is, it sometimes takes forever for it to figure out where I am. I don't know anything about VZnav because I refuse to pay for it.

GPS with google is autonomous. The data that is used is for the app itself (e.g. Map updates and loading). But once that's done, the location based service does not use agps to locate the user. This is why the app doesn't work very well indoors or in basements. There's no "cell triangulation" used. And its also why the 8330 and below still will not work accurately. It has no dual chip as does the storm series and tour.

Originally Posted by RicanMedic78

GPS with google is autonomous. The data that is used is for the app itself (e.g. Map updates and loading). But once that's done, the location based service does not use agps to locate the user. This is why the app doesn't work very well indoors or in basements. There's no "cell triangulation" used. And its also why the 8330 and below still will not work. It has no dual chip as does the storm series and tour.

Where are you getting this information? On my 9530, Google Maps does (and always did) use assisted GPS to rough in a location when traditional GPS isn't available.

That is so wrong. Google Maps absolutely needs data to update the map. Perhaps they have changed something with 4.02, but on the older version (last summer) the map data would not update at all. Sure my little location dot moved, but once it cleared the current screen, the map will go blank. What good is that? Yes, it requires Data to work.

I'm surprised how many people actually don't know this. when you use vz nav, it pinpoints you in a way that no other GPS can. This is because it uses GPS plus cellular triangulation (towers to locate satelite). Think about the 8330 as an example of what happens with a single agps that is locked. It will find you within 5000-1800 meters. The reason is, it uses data similar to smartwifi where the app locates your nearest tower based on your cell connection. Then from that limited info, it gives you a broad range as to where you are. Storm line devices and the tour use both agps plus autonomous (see the specs on rims site). The little that appears to be "triangulation" is actually 1 tower at work and not 3. And this is because Verizon does not allow this on their network.

Assisted GPS has nothing to do with cell site triangulation. It means that the phone gets GPS initialization information (such as the precise location of the satellites) from the cellular network rather than from the GPS satellites, as is the case for autonomous GPS. This is a significant amount of data, and thus is problematic if the GPS signal is too weak (like indoors). Doing the actual location fix requires a LOT less data, and thus can work with a lot weaker signal. Once the initialization info is obtained, no further info is required from the cellular system to get a fix. Whether you have the required map data on the phone corresponding to that location is another matter, and getting THAT requires a data connection. aGPS was originally designed to meet the needs of e911, which requires get a fix very quickly from a cold start with a problematic GPS signal.

Using the location of cell sites to supplement the GPS data is a Qualcomm extension to aGPS. The location of the cell sites plus whatever GPS fixes it can get are combined, so it can get a fix with REALLY bad GPS signals. Or none at all, relying solely on the triangulation, with a resulting decrease in resolution. Getting a location fix is essentially doing the intersection of some number of spheres (known distance from a known location in three dimensions), and getting enough to these so only one point results. The known references can either be GPS satellites or cell sites.

Originally Posted by CharlesH

Assisted GPS has nothing to do with cell site triangulation. It means that the phone gets GPS initialization information (such as the precise location of the satellites) from the cellular network rather than from the GPS satellites, as is the case for autonomous GPS. This is a significant amount of data, and thus is problematic if the GPS signal is too weak (like indoors). Doing the actual location fix requires a LOT less data, and thus can work with a lot weaker signal. Once the initialization info is obtained, no further info is required from the cellular system to get a fix. Whether you have the required map data on the phone corresponding to that location is another matter, and getting THAT requires a data connection. aGPS was originally designed to meet the needs of e911, which requires get a fix very quickly from a cold start with a problematic GPS signal.

Using the location of cell sites to supplement the GPS data is a Qualcomm extension to aGPS. The location of the cell sites plus whatever GPS fixes it can get are combined, so it can get a fix with REALLY bad GPS signals. Or none at all, relying solely on the triangulation, with a resulting decrease in resolution. Getting a location fix is essentially doing the intersection of some number of spheres (known distance from a known location in three dimensions), and getting enough to these so only one point results. The known references can either be GPS satellites or cell sites.

Thanks for the clarification. This is undoubtedly all information that Google Maps has access to, since it can do tower-only location along with the various GPS modes of operation.

ok, yesterday I was on the go a lot so I could not type well. But google maps DOES NOT use AGPS and this is a FACT! I will reference a recent comment from RIM on the 8830 when the GPS capability was in question at that time and you can decypher the difference in GPS with the statement below:

The BlackBerry 8830 smartphone houses a proprietary, autonomous GPS receiver. This
receiver is able to calculate the handheld's location relying solely on GPS
satellites with no input from cellular towers. While the device does have assisted
GPS, i.e. A-GPS capability, it houses a "full" GPS system similar in nature
to GPS systems used by GPS-only car kits and mobile devices. This is designed to
be accessible by second- and third-party applications such as BlackBerry Maps, Google
Maps, and TeleNav. Such programs do need a wireless data signal to download mapping
information, though they can figure out where the BlackBerry is in terms of latitude
and longitude with just the GPS signal.

The BlackBerry 8830 smartphone as released by Verizon has had this "full"
GPS capability disabled at a software level. Verizon has indicated that they plan
to release their own proprietary GPS mapping solution at a later time; possibly
VZ Navigator. AT&T and T-Mobile have both taken similar routes with their 8800
series handhelds; locking out GPS access for 3rd party programs and only enabling
access to the built-in receiver to the TeleNav program that they sell themselves.

If you would like Verizon to enable GPS functionality on the BlackBerry 8830, I
suggest you contact them and advise them as much.

Thank you again for contacting us, Dennis. If you have any questions or comments,
feel free to contact us.

Sincerely,

Adam
BlackBerry Customer Support
Research In Motion Limited

Google uses data to download maps exactly the same way that any 3rd party app would use data to function. That however does not mean that google wil have access to verizons network to assist in GPS functions and this is why on an 8330, your GPS location will be within 1800 to 5000 meters but with a new device with autonomous GPS, you will get a lock within 2 to 3 meters.

If the AGPS was unlocked, then 8330 users would have more accurate locks just as Tours and storms do

apps that have a GPS like function are really just searching for the closest location based on the tower currently connected to the phone (like smartwifi does). Heres an old link to the differences btwn GPS and AGPS:

http://www.wmexperts.com/articles/gp..._tutorial.html

Originally Posted by RicanMedic78

ok, yesterday I was on the go a lot so I could not type well. But google maps DOES NOT use AGPS and this is a FACT! I will reference a recent comment from RIM on the 8830 when the GPS capability was in question at that time and you can decypher the difference in GPS with the statement below:

OK then, it uses a magical satellite-free location service that allows it to fix a position using only the sheer willpower of the operator. Whatever.

this topic has been beat to death on many many forums, CB, device reviews, and there is a wealth of information online, some of which I have posted or provided information. Rather than be stubborn and claim to know what you do not, listen, investigate yourself, and come back with a less than sarcastic response as I am not dishing out the same to you nor do I care to argue about the inner workings of GPS with someone I do not know. Its not a personal thing for me, I am just giving facts on its capabilities. If you truly believe I am wrong, by all means, FIND THE INFO and leave the sarcasm where it belongs...

But you can't explain why Google maps, on my phone, works exactly like aGPS is advertised, and works the way qualcomm enhanced-gps is advertised...

I don't care, as long as it works, but your story just doesn't hold up.

Originally Posted by jeffmeden

But you can't explain why Google maps, on my phone, works exactly like aGPS is advertised, and works the way qualcomm enhanced-gps is advertised...

I don't care, as long as it works, but your story just doesn't hold up.

The phone has dual GPS (assisted and autonomous) and the one for 3rd party apps like google uses autonomous GPS (this was verizons way of giving us GPS capability for 3rd party apps without verizon lifting its own network privacy concerns, whatever they might be). That is why when you are indoors or in a basement and have a decent signal phone signal, you'll still get a large area range when google tries to locate you. But once you are outdoors, it locates you within meters again. AGPS is accurate despite the line of site which is why when you are using VZ navigator and are inside a tunnel or in a big city that blocks line of site, it still finds you accurately. Its different technology being used for both apps. This is a very well known observation on most mobile phone sites. I guess CB is so large, many threads or discussions are out of site to many users, especially those who gravitate only to a specific category discussion.

But if you want rock solid proof, just ask someone with a basic curve 8330 on verizon to try to use google maps and ask them what the range of their location lock is. Then ask them to use VZ Nav and see how accurate it is still, regardless of device. Then do it with your storm or a Tour.

Then after that, ask yourself why the inconsistancy with one device over another on the exact same network. its really simple! ;)