By Prince McLean

Published: 08:25 AM EST (05:25 AM PST)

Faster, and four other benefits to 3G

AT&T's 3G mobile network feels nearly as fast as WiFi, thanks in part to the iPhone's highly optimized Mobile Safari browser, Maps, and other apps that were designed to be quite usable even with a slower connection. In fact, the original iPhone could handily beat some other 3G phones in web page rendering speeds while only using EDGE. Having used the iPhone's web and Maps extensively with EDGE, and even falling back to the even slower GPRS data service in areas where EDGE isn't available, 3G is a very welcome upgrade.

Beyond data speeds, the second benefit to 3G reception is call quality, as 3G phone conversations are significantly clearer. That fact is bolstered by the iPhone 3G's improved mic and speaker, which even enable GSM conversations to sound better than the original iPhone. 

The third benefit to 3G is that it supports simultaneous voice and data; the original iPhone couldn't do a voice call while downloading data, but the iPhone 3G can (when it's in 3G coverage, of course). AT&T's competitors using Qualcom's 3G EVDO, including Spring and Verizon Wireless, are still constrained by that problem. Phones on their networks still can't browse the web while making a phone call, and won't be able to in the future either. The iPhone 3G's ability to handle voice and data at once is also supported by its smart interface, which makes it easy to look up information or do other things while on a phone call.  

A fourth benefit to 3G UMTS is that it has been adopted by international providers; AT&T's iPhone 3G users will be able to bring their phones to Europe or Japan and use them on roaming partner networks (although this can be expensive, particularly without an international data plan). Sprint and Verizon's 3G phones can only roam into Canada and Mexico; there is little or no CDMA EVDO service overseas. 

One last perk: the 3G UMTS protocol uses an entirely different signaling system than the current GSM, which prevents the signature "snapping" radio interference that plagues most audio equipment when GSM phones are in use nearby.

While 3G isn't the only new feature of the refreshed iPhone, living outside UMTS coverage might make it far less attractive to upgrade to the new phone. That reality has also created healthy resale demand for the original GSM iPhone, so if you're on the fence about the new features, you might consider the possibility of upgrading, reselling your existing iPhone for around $300, and making a profit on the deal overall.

Internal new hardware features: GPS

Outside of the new support for 3G UMTS mobile networks, the cheaper new iPhone 3G delivers an option for more Flash RAM storage (up to 16 GB) as well as GPS (Global Positioning System) location services, which can very accurately determine the user's latitude, longitude, and elevation using signals received from orbiting satellites. 

Existing iPhones use mobile towers and WiFi hotspots to determine their location, typically pin pointing the user within a roughly one block radius. In some areas, a lack of known WiFi base stations and limited mobile service might leave the Maps app drawing a huge (and rather worthless) city-sized radius around the user's given location. GPS enables the iPhone's Maps and any other location-aware applications to find a very accurate position from anywhere its satellite signals can be received.

GPS location acquisition on the iPhone 3G is very fast, in part because the unit performs a lookup using mobile and WiFi networks in parallel to predetermine the location. The iPhone 3G's ability to consult multiple sources of location information means it can determine a location faster than most standalone GPS units, which can require a minute of good signal reception to obtain enough information from satellites to determine their location. So called "Assisted GPS" is particularly suited to quickly determining your location in an environment that might obscure satellite signals, such as when in or around tall buildings.  

When location tracking is activated in Maps, a pulsating blue dot is drawn on your location, and you can watch the dot move down the block as you walk. Traveling in a vehicle, the accuracy is a bit more skittish; the dot might temporarily jump to side streets as you travel in a straight line. It seems that the faster you're traveling, the harder it is for the device to figure out exactly where you are. The iPhone 2.0 software calculates an accuracy margin and represents that as a blue area around the dot. While rapidly traveling north up Mission Street, we always remained in the blue area, but the dot jumped as far west as San Jose Avenue and then later a block east before bouncing back to Mission.



It's important to note that the 3G's GPS is included for location awareness; it is not a full replacement for dedicated, standalone GPS devices, and can't currently provide automated, turn-by-turn directions that most people associate with GPS. The upcoming iPhone 2.1 update appears to solve that problem, and both TeleNav and TomTom have announced plans to address the demand for advanced GPS features. On the other hand, its current integration with the Google-based Maps app also means you don't have to download and pay for maps for each location you visit, as is typically the case with GPS devices or other mobile phones that pack GPS features. Of course, the iPhone needs data service in order to download those free maps, as noted earlier.

GPS location data is also used by the iPhone 3G to "geo-tag" photos taken with the camera (but currently not screenshots), so that other applications (but not the iPhone itself!) can determine where the picture was taken by consulting its longitude and latitude metadata tags. Third party applications can also look up the iPhone's current location for various purposes; due to privacy concerns, the iPhone prompts the user to approve the use of location services before allowing new applications to track their location. 

On page 5 of 5: Internal new hardware feature drawbacks: battery life; When push comes to shove; and Unlimited apps.