Most GPS models come with internal map capabilities. Manufacturer provides maps with details up to street level in the hard drive. The menu option enables you to access the desired data. Comprehensive street level maps can help you identify the coordinates of the destination on the map by using just the name, or locate the destination on map by giving the coordinates. For some models you will have to subscribe to a plan to update the maps on an annual basis. Check out some models with internal map capabilities at: http://www.reviewgist.com/gps-devices-reviews?mapCapabilities=Internal



Some models provide map information in memory cards having detailed information of a particular region. Thus you will need extra cards if you have to store information for more coverage. Map cartridges are more flexible but can prove to be expensive. Check the few models at: http://www.reviewgist.com/gps-devices-reviews?mapCapabilities=Map+cartridges+%2F+Data+cards

Models which enable one to download the latest maps are also available. Check such models at:

http://www.reviewgist.com/gps-devices-reviews?mapCapabilities=Download+maps

Some brands provide map information in CD-ROM, DVD-ROM discs. Check out one such model at: http://www.reviewgist.com/gps-devices-reviews?mapCapabilities=DVD

Receiver type

There are 24 GPS satellites in six orbits around the earth. GPS receivers track these satellites to compute the information of your location, the bearing, distance and time left to reach destination and other route options. Since there are 12 satellites at a time in view, each of them is tracked continuously to generate the information. Latest GPS receivers marketed today are commonly 12 parallel channel receivers. You can find some such models at: http://www.reviewgist.com/gps-devices-reviews?receiverType=Parallel-Channel+%2812%29

The associated advantages of tracking more satellites are:

faster cold start

regular initialization

better reception

do not require an external antenna if you are in an open vehicle

Other receiver types are:

20 parallel channel receivers http://www.reviewgist.com/gps-devices-reviews?receiverType=Parallel-Channel+%2820%29

16 parallel channel receivers http://www.reviewgist.com/gps-devices-reviews?receiverType=Parallel-Channel+%2816%29

14 parallel channel receivers http://www.reviewgist.com/gps-devices-reviews?receiverType=Parallel-Channel+%2814%29

Display size

Large displays are a visual treat when you consider buying TVs but not the same when it comes to buying a GPS. The map on the display gives you information regarding:

current location

where next turn is

name of street you are turning onto

estimated time of arrival

While driving, casting your glance away a second longer can prove to be risky, hence a device with a smaller screen will be advantageous. The display should be easy to read irrespective of surroundings. The navigation aids come in various sizes. Some units with screen size as big as 7in. (http://www.reviewgist.com/gps-devices-reviews?displaySize=7+in.) enable you to get connected to external video devices. Some hand held ones are as small as 1.5in.X 0.9in. (http://www.reviewgist.com/gps-devices-reviews?displaySize=1.5+in.+x+0.9+in.) Some of the convenient, easy to read GPS are:

3.5 in. (http://www.reviewgist.com/gps-devices-reviews?displaySize=3.5+in.)

2.8 in. x 2.1 in. (http://www.reviewgist.com/gps-devices-reviews?displaySize=2.8+in.+x+2.1+in.)

Resolution

Screen resolution decides how clearly you can see and read in broad daylight. Color, glare free LCDs are soothing to the eyes. High end models have color screens which gives information about weather and terrain. Some GPS units with different resolutions are:

320x240 http://www.reviewgist.com/gps-devices-reviews?resolutions=320+X+240

480x272 http://www.reviewgist.com/gps-devices-reviews?resolutions=480+x+272

PC Interface

The portable models have a USB or serial ports which gets you connected to a PC. It enables you to download latest maps and system software. GPS units with USB and serial ports can be found at:

USB: http://www.reviewgist.com/gps-devices-reviews?pcInterface=USB

Serial port: http://www.reviewgist.com/gps-devices-reviews?pcInterface=Serial+RS-232

Bluetooth GPS that communicates with mobile device wirelessly are also available. Some can be found at: http://www.reviewgist.com/gps-devices-reviews?pcInterface=Bluetooth+Wireless+Technology

Built-in memory

With larger memory space one can store more route information and waypoints. Units with software that can transfer data from the unit to a PC can be used to gather more data than it can hold. So depending on how much map data and information you wish to store, you can select the units with the required memory space. You get various models with wide range of built-in memory space.

1 to 30MB http://www.reviewgist.com/gps-devices-reviews?builtInmemory=1-to-30

30 to 512MB http://www.reviewgist.com/gps-devices-reviews?builtInmemory=30-to-512

512 to 2500MB http://www.reviewgist.com/gps-devices-reviews?builtInmemory=512-to-2500

2500 to 40000MB http://www.reviewgist.com/gps-devices-reviews?builtInmemory=2500-to-40000

Antennas

External antennas are used when stronger signals are needed. If in a vehicle the system cannot be placed near the window, external Antenna hookups can prove to be ideal solution. Choice of external hookups is most practical for hiking under heavy tree cover, under tall buildings or in any place which doesn't have a good view of sky. GPS devices with external antenna hookup can be found at: http://www.reviewgist.com/gps-devices-reviews?antenna=External+Antenna+Hookup

Built-in antennas are less prone to breakage and can communicate with more satellites. Some such devices are available at:

http://www.reviewgist.com/gps-devices-reviews?antenna=Built-in

Quadrifilar Helix- This is also an external antenna useful for situations where open sky is limited. Check the models at:

http://www.reviewgist.com/gps-devices-reviews?antenna=Quadrifilar+Helix

Flip up antennas too give strong performance. Some such models are : http://www.reviewgist.com/gps-devices-reviews?antenna=Flip-up

Price

This is one factor not to be compromised on, if you don't wish yourself or your loved ones to get lost in the maze of roads. The technology in this field has developed rapidly and the old models which are cheaper may have crowded maps, or confusing menu options. Latest models high on price have more detailed maps. Of course, lesser the features lesser will be the cost. If you don't need features like live traffic data or weather data, don't invest money in models offering these features. Features like speech recognition for hands free operation, 3D maps, and information on fuel prices all come for additional price.

Under $200- http://www.reviewgist.com/gps-devices-reviews?Price=59.5-to-199.99.You get good light weight portable navigation units in this range. Maps look great with reasonably timely route recalculations. Good value for money! Those of you looking for more memory space may check out models at higher range.

Between $200 to $312- You get better performance and features like anti glare, touch screen with good resolution. You also get good in-built memory space and battery life. http://www.reviewgist.com/gps-devices-reviews?Price=199.99-to-311.99

Between $312 to $416- Good screen settings, voice guided directions and overall good performance. http://www.reviewgist.com/gps-devices-reviews?Price=311.99-to-415.45

Between $416 to $1172- Accurate route guidance, easy to use and compatibility with Bluetooth cell phones are some attractive features of devices in the price range. http://www.reviewgist.com/gps-devices-reviews?Price=415.45-to-1171.78

Brands

There are various manufacturers manufacturing GPS units with different features to suit a wide range of customers. The major brands available today are:

Garmin has many models of handheld and mounted types. Check its models at: http://www.reviewgist.com/gps-devices-reviews?BrandName=Garmin

Magellan: http://www.reviewgist.com/gps-devices-reviews?BrandName=Magellan

Mitac: http://www.reviewgist.com/gps-devices-reviews?BrandName=Mitac

Lowrance: http://www.reviewgist.com/gps-devices-reviews?BrandName=Lowrance