But then how will they track you
unless they upload all the intervening Position Metadata when you reconnect to the Internet again?
Google has updated its offline functionality for its Maps application allowing wayward or data-bereft travelers the opportunity to download regional maps at WiFi hotspots and receive turn-by-turn navigation without an internet connection. The offline feature is an older feature that has been upgraded to include directions and …
'unless they upload all the intervening Position Metadata when you reconnect to the Internet again?
Oh they do, I turned my phone's GPS on 5 or 6 times on a transatlantic flight to check if they did. After landing and getting to my friends I checked out my Google location history and sure enough rather than a great circle route from London to LA it joined the dots of where I'd had the GPS on.
It does. A compass (usually via tri-axial magnetometer) and tri-axial accelerometer is enough to maintain reckoning until you emerge, and you'll find most phones of note will have these features standard these days. Even my old Nokia N95 had a compass; don't know about the accelerometer, though.
Not really. Unless you recalibrate the compass when you step into your big steel box the compass isn't great but passable in some situations. The accelerometer will not tell you much about your current speed and isn't clever enough to recognise exactly how fast you are going by converting all the little decelerations and accelerations into a speed differential based upon your car profile.
With Sat Nav that I have used it generally assumes you're travelling at a similar constant speed throughout the tunnel from where you entered it and you took the turns you were supposed to while in there.
What DaLo said.
Assuming you are travelling at roughly constant speed in a tunnel is easy. Taking the integral of acceleration to get velocity, and again to get location just makes the sensor errors too big to be practical.... apparently, according to this fella who is smarter than I am on a Google Tech talk: (23 minutes in)
Not if you work in relative terms. GPS will give you orientation and current velocity up to the point you're cut off. Just read the magnetometers and accelerometers at that point to get your baseline reference, then work from there until you regain the signal (upon exiting the tunnel). It also helps that tunnels are naturally constrained so a mapper will know if the sensors start to drift.
Regardless it isn't going to work. If you had a fully calibrated magnetometer and accelerometer specific to that device and your vehicle profile then you could approach a level of accuracy but in reality this would happen on a mobile phone as there are too many variations so why bother.
If the tunnel is "naturally constrained" then you don't need navigation. However many tunnels aren't, some can be 25Km long and they can have roundabouts and other 'normal' road layouts within them, including different elevated sections.
ANyway this was about whether phones have internal guidance (rather than whether they have features that could be used to create pseudo-internal guidance). Easy to test, go through a large tunnel with multiple layouts and try changing speed significantly and missing your route's exit on an internal roundabout. Watch as your satnav waits at your expected exit from the tunnel at the expected time before rapidly switching it when you come out in a different place.
>Just read the magnetometers and accelerometers at that point to get your baseline reference, then work from there until you regain the signal
The point is that there is too much cumulative noise on smartphone accelerometers to use them alone for ready-reckoning. And yes, smartphones aren't stupid, and will use a combination of inputs to get a location fix.
The video, about fusing different sensor inputs, is interesting.
What makes you think you can only download cities?
Offline maps (but not offline navigation) has been in the last few versions of Google Maps - though made last obvious in the previous version. The area you can download is limited by an arbitrary number of MB. Rural areas work fine.
Hardly, 375MB for SanFran alone.
Sounds like about 100GB for the UK and the same for Spain.
I have Spain and he UK too, 1GB to be sure but completely doable.
Also, one can download regions like Castilla de la Mancha alone for instance.
I suspect the fact that one is a bolted-on raster-scan afterthought and the other is a fully featured vectored mapping system with navigation etc.
Given the amount of times I have had no coverage in the UK where knowing my location is important if not quite life-threatening (although still entirely possible in the wilds here), I can only assume that goes double for Australia.
I honestly don't know how almost everyone makes do with Google/Apple maps, I guess most people are happy with that pixelly, slow nightmare.
For me, it is a showstopper and adding this small improvement which requires forward planning and more delays for data download ahead of time isn't going to make me think for even a moment about switching.
Of course, I would probably use HERE maps on Android if I had to use Android, even though it is not as extensive as the WinPho version I believe.
After all Browser then Maps are the Apps that matter (to me) after the obvious Phone/Message ones.
>Given the amount of times I have had no coverage in the UK where knowing my location is important if not quite life-threatening (although still entirely possible in the wilds here),
I'm sure you know this, but mountain rescue teams will welcome people not taking a false sense of security from carrying a mobile phone.
If you can't use redundant, dedicated hardware (which is weather-proof and battery frugal) such as a paper map and a Garmin GPS, at least use a paid-for mapping app that it is fit for purpose. If in the wilds, turn your data off, otherwise your phone will eat through its battery very quickly searching in vain for a signal.
I recently swapped off Windows Phone (been using it since I got a HD7). Been using HERE maps since I got a 920. Great maps. Installed them on Android, and they're damn near as good. Couple of features I never used like the links to HERE transit etc don't work (But I've not even checked for those apps on Android). I'd actually pay for this if they started charging on Android, they're actually the best balance of usability and functionality I've found.
I always want to have a paper map with me as a backup to the gadgets. I can then also plan a rough route using the map before I start to check the sanity of any instructions given me by a phone/satnav.
However, if the choice is between getting turn by turn instructions from the Lumia or from the wife "reading" the map I know which I would prefer...
How can San-Fran be 375 odd mb, when on Here maps on Nokia is little more than that for the whole of the UK, and I 've found it to be far more acurate than Google (hint: it doesn't try to get me to park on hard shoulders of motorways).
I presume it's downloaded place names as well, such as the local Starbucks or Samsung shop.
HERE maps also has places, phone numbers and web sites while used offline.
Just fewer of them, the most common, fuel stations, hotels, McDs type places.
It also renders city centre buildings in 3D (funky grey boxes for most), changing depending on the angle of view, which is completely user controlled with rotate and zoom etc. (on WinPho at least)
The buildings flatten and rise as required, very slick, especially when driving because the zoom level changes with car speed automatically.
And then of course, some buildings of note (try London or Sydney) are fully rendered in 3D and colour/detail.
Also worth a mention is the fact that they detail the layout and contents of places like airports, shopping centres/malls and train stations and even University campuses with plan views showing (say) each individual store, terminal, platform or department, directories of all the stores by name, location and details. This includes detail like where water fountains are and staircase locations and is remarkable.
I love the fact that one can slide a finger on the 'Floor' button and show the Stores for each floor as they stack one above the other (try Harrods, it has a lot of floors).
And yes, all in the off-line mode as well, which is bloody useful when embedded deep in an airport or Harrods for that matter.
It is probably why the map size increases steadily as they increase the number of featured buildings and installations.
Could it be that they subvert the new functionality by making it download the full satellite imagery and street view for an area? That's the only way I can see they could come anywhere near those figures.
Nokia maps work a lot better and require only very modest data volumes. Or at least did, in the days when Nokia sold some excellent phones.
 Talking about my beloved E71 there.
There are limits for the size of areas that can be captured for offline viewing: this reporter's attempts to download Australia, Britain, and the continental United States failed, for example.
So downloading *half the planet failed :) I like your testing procedure, sounds scarily familiar ;)
*Jeez I know its not really half !!!!
"Update rids backpackers of reliance on ruinous data roaming"
According to the Beeb's story, "while the app provides driving directions, it will not offer walking or public transport-based routes."
You can of course still download the maps, and use GPS to locate yourself on them. Though since "Owners cannot switch to a satellite view", that may be of limited value in the outback.
Correct, Google Maps omits UK footpaths for example - which makes it an inaccurate walking planner, don't be misled by the walkers route planning icon!
So I used Openstreetmap for walking as a free solution, clumsy though it is.
When Google Maps introduces footpaths it will be a game changer, and i believe Google could automatically derive most UK walking routes by collecting data from participating Google Maps users as they walk about. Next thing you know we'll see folks walking about with a helmet on with a rotating camera atop, in advance of 'Path View'.
With the right software, I've had "offline" capability on not only Google maps, but a number of other map suppliers too. Useful when google maps might not be the most 'asthetically pleasing' of the map options too. Technically, I would not be limited to their suggested sizes either. I can grab sections at a time, perhaps days apart, and merge it all together when I'm done.
I think none of the main mapping systems deal with off-road well at all.
Bing maps can display Ordinance Survey maps in the UK and I used to have an app which downloaded and stitched required areas for hikes using these, really, really good, maps (post boxes and cairns might be present for instance).
Now I use an app which does the same with OSM or HikeandBike maps, pretty good alternatives although I still miss the OS ones badly.
Coupled with a GPX file one can take rougher, less-well-known paths knowing the way even in fog and mist, as happened recently to me, trudging across bog basically in roughly the right direction modified only by the ground conditions.
Given the data set sizes required, this will remain the case for a while.
I would love to see if the OS can build a vectored version of their system though, enormous still but smaller overall perhaps than raster (and always jag-less of course).
Situation has improved, maps are cheaper than buying paper as you can just buy the tiles you need. Tiles can be bought at Explorer or Landranger, 70p per land ranger "tile" and ~£2 for explorer tile.
Using "OS MapFinder", the GPS tracker plonks you right onto the OS map, makes navigating a lot quicker, as you just need to do a few point of reference checks to make sure the GPS isn't telling porkies, rather than starting from scratch.
The confusingly similar "turn by turn" app "OS Maps" isn't bad either although not as many features as others.
Both allow you to plot / record routes etc.
Would be useful if the maps were accurate away from roads and contained rights of way information. Google maps is missing a lot of footpaths, bridleways and byways, and doesn't have accurate right of way information on those that are included. Round here some tracks with no public right of way are indistinguishable from roads or other public rights of way, equally some rights of way are missing or innacurately mapped. It falls behind OSM in a lot of respects even though Google maps had a head start and an awful lot more funding.
Google may do some clever stuff, but maps is frankly crap when compared with other products, even when you're online. The offline capability is so far behind a lot of the competition it's pitiful.
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