My take on the iPhone 3G, especially its GPS
The buying experience
It was a given that at some point, I would get myself an iPhone. So why delay the inevitable? I went to the new Telefónica "flagship" store at the Gran Via in Madrid that opened on iPhone day. I got there at 8.40 with some 150 people in line already. The store opened at 10.00 and the line started moving forward incredibly slowly. At 13.30 it started to dawn on me that this was probably going to take all day. It did. After being in the sun during the hottest hours of the day I finally got inside the store at 15.30, but then it took another three hours before it was my turn. Apparently some servers somewhere melted down. But at 18.50 I finally had my iPhone. I'm glad I have it, but I'm not going to let something like this happen ever again. And had I known it would take this long, I'd never done this.
Activation
One of the weird things about this launch is that people were supposed to leave the store with a working phone. In the US, at least. In Spain, I got a SIM package and a phone, both of which were dutifully scanned and presumably linked together in the cloud, and then a little flyer telling me how to activate the iPhone 3G at home using iTunes. Obviously giving people a phone that is ready to make calls is hardly a bad thing, but Apple and AT&T must have realized that this would add extra time in the shops, even if they didn't foresee the massive activation issues that ensued.
What I think is that either Apple or AT&T wants to work towards a future where you can get an iPhone even if you don't have a computer. Although strictly, this would be possible today if the phone is activated in the store, that would be inviting trouble because content bought from the iTunes or apps stores can't be backed up and will invariably be lost at some point. However, it shouldn't be too troublesome to use an iPhone with a computer, but without an internet connection. That only means you can't download software updates. The requirements for the iPhone do list a computer, but not an internet connection. However, the box for my Spanish iPhone does list an internet connection as a requirement. (No, the iPhone 3G's own connection to the internet doesn't count.)
The iPhone 3G vs the iPod Touch
I never had an original iPhone, but only an iPod Touch, so many features that aren't actually new are new to me. The iPod functionality is slightly worse, despite the physical volume buttons. On the Touch video and music are separate things, that each remember what you were playing independently. On the iPhone 3G video can be found in a little corner of the iPod application. What's really annoying is that double-pressing the home button will only bring up the overlay iPod controls when you're playing audio. If not, then you'll be transported to the iPhone app. The volume goes much higher on the phone than on the touch, which is a good thing if you have headphones that are on the quiet side. I love being able to play podcasts over the speaker! Another very good thing: calendar month view will now start on monday rather than sunday. This was driving me crazy.
GPS
I've been trying to find out as much as I can about the GPS functionality, or rather, the location services. Although many applications in the app store can make use of location services, only two of the built-in applications do the same: maps and the camera. Both will ask you whether they can use your location information when you start—most of the time. It seems like after a few times, they don't bother anymore. However, it also looks like there is a bug in the maps application, and possibly also in the camera: when you've tried to determine your location unsuccessfully a few times, it won't work anymore after that, even if you have a clear view of a sky full of GPS satellites. A power cycle will clear this up.
It's surprising to see how quickly the iPhone can determine its position when there is good GPS coverage. I'm not sure if it's fast enough to embed location information in a photo if you open up the camera app and immediately press the virtual shutter, though. Unfortunately, you only get to find out when you sync and bring up the EXIF data on the computer. I have a few photos where there is a location in degrees and minutes, but the seconds are both zero. I'm guessing this happens when there is no GPS info, but only less precise location data from cell towers or wifi networks. One minute is an accuracy within a nautical mile (1852 meters). So far I haven't seen the GPS altitude filled in, maybe this will happen with photos taken with a strong GPS signal.
In the maps application, if you press the little widget in the bottom left corner, it turns blue and the phone starts homing in on your location. (Pressing it again doesn't necessarily stop this, though.) If you see a circle, it's using cell towers or wifi signals, but when it gets a GPS lock you see a blue dot that periodically pulses. It also has a larger blueish area around it that indicates the accuracy of the location fix. When you start moving, the blue dot moves with you, with a slight delay. In "search" mode, the dot moves all over the place, often 5 - 15 meters from the actual location. (Or are Google's maps inaccurate?) However, in "directions" mode, the dot tries to stick to streets in general, and the calculated route in particular. Unfortunately, the directions still have to be advanced by hand, the blue dot isn't helpful in this regard. I'm thinking that quickly recalculating the route from your current location once every few minutes makes more sense than meticulously trying to follow a previously calculated route.
In order to see if the GPS would also work unassisted, I turned on flight mode. No go. Turning wifi back on also didn't help. Apparently the GPS receiver is only powered when the cellular network is operational. However, by turning the iPhone off and on and not unlocking the SIM, the phone can't connect to the cell network but the cellular radio is operational. (You can make calls to 911 or 112 in this mode.) The iPhone didn't have any trouble locking on to a GPS location without any cellular or wifi internet access. In fact, it's so fast that I can't believe it's doing an actual GPS cold start. This can take many minutes on older GPS receivers. I'm guessing at least some GPS information is still cached. Looks like I'll have to investigate this further. Note that the Google map data is also cached, so if you bring up the area that you're going to visit before you lose your internet connectivity, you can then use the GPS to see where you are without network access.
Permalink - posted 2008-07-14