Important features for a  GPS to be used for Automobile Navigation:
Revised 6 September 2004   by Joe Mehaffey

What features are important for a particular use are a very personal thing.  And..  The features needed for automobile navigation use are a bit  different  from those needed for hiking navigation use.  Below are my "essential automotive navigation feature list" of GPS receiver features.

(I omitted features that are present in ALL receivers.)

1) Address to address Routing:  We believe that any GPS you buy for automobile use from this time forward should have the built in capability for automatically guiding you to a specific street address.   (Kits which INCLUDE mapping software are indicated (*).  The automatic car navigation  feature is now present in low and medium priced Garmin  (such as  GPS-V, GPS-60C, GPS76CS,  StreetPilot III(*), StreetPilot 2610/2620/2650/2660(*), GPS276C, GPS295,  iQue 3600(*) and Quest(*)) and the Magellan RoadMate 500/700,(*) Sportrak Pro, GOLD and PLATINUM models.   Models without the (*) require optional at extra cost mapping software.    The new TomTom "GO(*)" (a competitor to the Roadmate and StreetPilot 26xx) also has automatic car route generation.   Alpine and Magellan PathMaster (750NAV(*)), VDO Dayton(*) and other automobile built in  navigation systems ($1800 and up) have this feature.  The Garmin StreetPilot 2610, Magellan 500/700, Magellan Meridian/Sportrak and StreetPilot III, G60C, G76C, and Vista/Legend Color, iQue, Quest and GPS-V have the address to address routing and at a price of about $300 to about $1200 depending on model.  Garmin's  GPS-V, G60C, G76CS, Vista/Legend (COLOR only) and the Magellan Meridian and Sportrak models all have optional address-to-address routing,  but  with "beep" prompting and no voice prompts.   Units providing VOICE PROMPTS for turns and guidance include: Garmin StreetPilot 2610/20/50/60, StreetPilot III, Quest, Magellan RoadMate,  750NAV, TomTom "GO", VDO Dayton,  Alpine,  and many OEM automobile navigation systems.    Delorme StreetAtlas 2004,  has a good implementations of address-to-address routing and can be used stand alone at reasonable cost IF you already have a laptop computer.  In the Delorme case we recommend a standard handheld GPS in place of the Delorme GPS receiver.
2) Built in road Maps: Built in  and detailed road map displays of your area of interest are an essential feature of a good Automobile GPS receiver.
3) Route capability:  Automatic Destination Routing is a standard feature on any good (modern) Car Navigator GPS.
4) Waypoints:  Some Car Navigators use ONLY street addresses, road intersections, Points of Interest, Restaurants and such.  This is a pretty good minimum requirement.  All Garmin models offer "mark waypoint" capability for locations and the ability to "point" to a desired destination on a map.  We like these a bit better,  but this feature are not essential.
5) Datums:   Many if not most Automobile GPS receivers (SP and ColorMap among many others) have only WGS-84 datum.  (-and they do not need anything else when they are loaded with ref datum WGS-84 maps.)
6) Mounting:  Make sure the unit you select is capable of being mounted neatly and securely in/on  your vehicle.
7) Turn Here:  Make sure the unit gives you the signal you want for a "next turn".  The best units have voice and visual prompts for turns.
8) 12 channel parallel receiver system:  Needed for best reception in difficult terrain and tree cover.
9) Dead Reckoning:  Most of us do not drive often in high rise central city areas.  If you do,  you will want to consider units with a built in Gyro capability as the best GPS will loose lock in dense high rise areas.  Garmin's SP2650/2660 and the VDO Dayton are examples of these.
Maps:  Make sure that the unit you select has user uploadable maps (or maps on its built in CDROM, CF card, MiniHD, or other memory) for the area you need.
11) TrackBack and other "standard" GPS features are not universally available in Car Navigator units.  When you think about it,  "tracking back" the same way you came can be hazardous in a car navigator!  These units are designed to generate a new route for you on each new route selected.
12) The OEM car navigators are "engineered into the dash", look great and perform the basic car guidance functions reliably.  However, these OEM units generally  cost more and offer inferior features and performance as compared with  the StreetPilot 26XX and Magellan RoadMate units.  We have had a number of reports of users unable to obtain map updates for OEM car navigation systems.  Others have complained of the high cost of map updates for the OEM installed systems.   We suggest you try and obtain a written guarantee of map updates for 5 years as a condition of buying an OEM car navigator.   We suggest a discussion of the price of map updates is a good idea as well.

Useful but not essential features:
1) An external amplified antenna can be useful to allow full sky view and maximum position accuracy for a GPS used in your car.  BUT:  Most modern GPS receivers work OK without one.  Try without before you buy. If you think you might NEED this feature later,  make sure to buy a unit with external antenna port.
2) Screen: A larger Screen than available on handhelds is a nice option.  Color Screens are useful for getting more map information from the unit "in a glance".  Some models have "transreflective" screens and these models do better in bright sunlight than other screen types.
3) We think that "almost" everyone will want at least 64 megs of map memory in a car navigator.  Many will want much more map memory either in the form of a DVD drive, Hard Drive or large CF memory card.  Sixty-four megs will hold the map of California or New York.  It takes about 1200 MegaBytes to hold detailed road maps of the entire USA.  1450 Megabytes for Garmin's 2610 for all USA and (available) Canada maps.

<>SOME of the lower cost units we consider most suitable for automobile navigation include (in no particular order):
Magellan RoadMate 500/(@#+)  700 (@!+), Meridian GOLD(@#+%), PLATINUM(@#+%) and Sportrak Pro(@~%)<> with DirectRoute,   StreetPilot 2610/2650 (@#+),  2620/2660(@!+),      iQue 3600 PDA/GPS (@#+),   GPS76CS(@~+%)Garmin GPS-V(@&+%)Garmin GPS-60C(@~+%)StreetPilot III(@&+)Vista/Legend COLOR(@^+%)   
Click on blue links above to visit our product review of a particular model.

More expensive but nice:  Magellan 750Nav(@!+),  VDO Dayton (formerly Philips-Carin)(@!+),     Alpine(@!+)

Notes:(@) These units offer automatic address to address routing within the unit.
            (^)  These units offer fixed map memory in the range of 19megs to 32 megs.
            (~)  These units offer FIXED map memory size in the range of 50megs to 128megs.
            (&) These units have optional memory module,  8 megs to 256 megs available.

            (#)  These units have available as option or standard, large memory to 2GB in form of CF or SD Memory plus a fast processor.
            (!)   These more expensive units have  either a Hard Drive, CDROM (or DVD) drive for map storage and a fast processor.
            (+)  These units have (or have as an option) an external antenna capability.
            (%)These units have a smaller screen than other models listed.

Discount Internet GPS Vendors> HERE 
(Note:  Joe and Jack do not permit vendors with unresolved customer complaints that we are aware of  to advertise on our website.)

If you have a suggested unit that you think should be added to my list,  please let me know.

Email to:  Joe Mehaffey

Dale DePriest presents addition ideas and information on how to pick out your first GPS Receiver,  CLICK HERE

RETURN to Joe and Jack's GPS Information Site, CLICK HERE.