about phabtom alert

Give us a better idea of what you are after, please.

I wasn't aware that any Phantom Alert .com product was free.

You cannot add or use your own POI's as it connects to a website for use.

If your Droid has a internet interruption so will your service.

Service relies heavy on USER input! You are limited to what the Website offer and what has been reported by it's user.

The service range from $9.99 a month to $99 lifetime.

You can get a FULL SERVICE GPS for what you will pay there!

In my opinion... Get a GPS!!!
I would recommend the 765T as it is priced right and FULL of FEATURES.
If you have any more questions let me know?

you mean the function is from internet ?

You can download the POI's to a GPS... But if you use it on a Droid phone then you are very limited.

The POI's offered can be downloaded free from this and other sites.

The cost in my opinion just don't make Sense when you look at what is offered here and there as well as other POI sites.

You can try the one month service if you like and cancel if it's not what you expected.

What Exactly are you looking for or need that you see there and is not here?

I will help if I can.

Dedicated GPS > Phone gps.

Garminfone fills this niche nicely, I think...

Aren't phone GPS units relying on cell towers rather than satellites?

In which case, while they might rock within cities, they'd become useless in the open country where you might only be in range of a single tower?

Or are these units receiving both sets of signals?

The math used to determine position requires at least three satellites acquired and mine doesn't acknowledge acquisition until I have five or more.

Not necessarily.

My BlackBerry Tour 9630 has a very accurate (stand alone) GPS chip.

Smart phones have full standalone GPSr chips in them nowadays. However, to save power and to increase battery life, the GPS receiver is not always turned on. I have Google Latitude enabled on my phone. If I don't have Google Maps or any other application that uses the GPSr running on the phone, then my position as viewed on Google Maps (by anyone with whom I share my location) is keyed to the cell towers closest to me, and the radius of uncertainty as shown on the map can be a couple of thousand feet or more - unsuitable for navigation. However, once I fire up any application that uses the GPSr, and the satellites are acquired, my exact (almost) position is shown on the map with a radius of uncertainty of 10's of feet.

I'm assuming that dialing 911 will cause the phone to turn on the GPSr.

I haven't found the option on my phone to always keep the GPSr turned on. It is probably not an option because the standby time might be reduced to much less than a day - not good for a phone.

Cellphones have never gotten position info by triangulation from nearby cell towers. Position info has always been from satellites, just like our GPSrs. In the past, some phones did not have GPS. Almost every cellphone now has satellite GPS which is used for Enhanced 911. The coordinates of the phone is displayed to the 911 dispatcher.

dobs108

I admittedly don't know much about cell phone technology and from what I have read, I think it is correct that the newer high-end phones have satelllite bsased GPS receivers in addition to the cellular circuitry. But your statement doesn't seem to agree with this wiki article: http://en.wikipedia.org/wiki/Mobile_phone_tracking

Look at the dates on the Wiki footnotes - they are stoneage in cellphone years. Wiki is talking about the police tracking a phone, which CAN be done by triangulation. But if the phone is GPS-equipped, which today means almost every phone, why use triangulation anymore? By the way, your phone can have GPS even if there is nothing in the manual or software to indicate that. It is needed and required by law for Enhanced 911.

dobs108

A couple of years ago, Vonage advertised a low-cost cellphone service, but it was discovered that their network did not provide Enhanced 911 coordinate info to the 911 dispatcher, even thought the phones themselves did provide the position. The feds intervened, and today the Vonage network has Enhanced 911.

dobs108

You're still not correct regarding cell phones. Yes the phones have chips. Yes, the towers all have GPS antennas for timing. But the cellular network doesn't use GpS positional data from either. The CDMA network is the closest to using positional data from the phone, but the GSM network still estimates position based on which of the antennas is receiving the signal and the strength of the signal. Positions can be estimated to within 100 meters using 3 towers, within 300 meters with one tower.

It comes down to the technology in the network, not the components.

Triangulation can estimate a position at best within 100 meters, or in the worst case within a third of a mile! Neither one is close enough for Enhanced 911. If there are areas in the US whose only coverage is GSM, they do not have Enhanced 911. We are up to 3G and now even 4G, and the position is accurate because the GPS track of the phone is being transmitted (and saved) on the network at all times.

This much is known publicly - When a cell phone makes a 911 call, the position is displayed to the dispatcher with GPS accuracy. What is not generally known is that the GPS track is saved (on the network, not on the phone) and can be accessed in real time or in the future by the police or others by court order.

Employers who supply your work-related cell phone have access to your track because they own the phone. This is not limited to the latest high-end phones, because the government has mandated that phones have Enhanced 911 capability.

dobs108

Three phones ago, the manual of my low-tech (Sprint) flip-phone mentioned it had a real GPSr chip in it for E911 purposes. Sprint also sold a crude navigation service then based on a Java application that ran on the phone. Anyway, just comparing how much faster the battery drains on my current smart phone when an application is using the GPSr leads me to believe that normally the GPSr is powered down, and the phone uses the cell ID for locating itself during those times. (Of course the network always knows which sectors the phone is talking to regardless of whether the phone itself does). This was consistent with my observed behavior of Google Latitude.

To confirm this, I did a little Googling, and found the following:

http://www.popularmechanics.com/technology/how-to/4258805

"A 911 call triggers the chip, and the coordinates are sent to the local PSAP [Public Safety Answering Point]," says Verizon spokeswoman Debra Lewis. This system is generally accurate within 160 to 500 ft.

"While the only way to turn this tracking off is to shut down your phone, it is not actually activated unless you call 911. If you think this raises privacy concerns, just consider the nature of mobile phones, which are continually connecting to towers. Records are kept of every tower your phone communicates with. While it may not be as precise as true GPS, this information is being recorded any time your phone is on."

The same article also states that Sprint and Verizon phones (which use CDMA technology) have real GPSr receivers in them, but not necessarily for other carriers like AT&T that use GSM/UMTS technology. I presume because GSM triangulation is more accurate than CDMA?

Back to my question on the behavior of Google Latitude, I found the official answer from Google:

http://www.google.com/support/mobile/bin/answer.py?hl=en&ans...

How often does the location update, and when is the GPSr used rather than the cell ID? It depends .. on battery life, if you are moving, and how fast. Background updates keep the GPSr turned off to preserve battery life.