purplesoup

I love my Motorola Droid, especially the built-in Google Navigation (still in beta).  It is probably the single most useful aspect of my phone.  The traffic times are pretty accurate so I use it even when I'm travelling to places I go all the time. 

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That said, I can't figure out how it determines some of the routes it uses and it makes me leery of using it in places I've never been before.  As an example I'll use my journey from work to the Irving Park Chicago Dance location.  I take this trip 3-4 times a week and kind of know the ins and outs of the traffic pitfalls.

My basic route is Rt 43 to Deerpath to Rt 41 to I-94, exit I-94 at Cicero, go the ~ 0.5 miles to Elston and take Elston to Irving Park Road.  Given the vagaries of Chicago traffic, this can take as little as 45 minutes to an hour and 45 minutes.

When I first got the Droid in November, this is the route Google Nav suggested.  About two months later it started telling me to take I-94 all the way.  I thought it was possibly taking traffic into consideration and there was a problem on my regular route, so I did a check for "alternate routes".  The travel times only differed by a few minutes, but upon closer inspection the route I thought was my regular route actually had me staying on Rt 41 the whole time.  My regular route was a good 10 – 15 minutes faster than any of the alternates but it will never give me that option.  It always reroutes to take me onto surface streets with a longer travel time, telling me to exit I-94 at every exit along the way.

Here are the most cracked-out examples:

• Yesterday, when I had to stop for gas before heading out, I went to a gas station a bit south of Rt 137 on Rt 41.  Google Nav kept insisting I turn right at just about every opportunity as I headed south on Rt 41.  Finally, at about the third right turn option, when stopped at a light, I checked the route details.  It wanted me to turn right at Half-Day Road, go 1.6 miles make a U-Turn, come back the 1.6 miles and turn right onto…you guessed it, Rt 41!  In what universe would that route be faster?

• Last weekend, when I was heading to the studio on Saturday morning, it was doing the surface street thing as usual, but when I passed it's suggestion of exiting at Old Orchard Road, it chose the next exit, Dempster Road.  This time it suggested I get off at Dempster, go east, get back on I-94 going north, get off at Old Orchard Road and take surface streets.  Based on the estimated times it gave me, that route would have added 15 minutes to my drive.

• Finally it thinks my house is about 0.3 miles from where it really is, which is odd since Google Maps used to pinpoint it exactly.  I just checked and regular Google Maps is off too.

 These are reasons we didn't quite trust the directions it gave us when travelling in rural Minnesota recently, so we did some trial and error and finally got where we were going.  After all was said and done, it turns out that Google had pinpointed the location within feet, but had a rather circuitous route for getting us there.  And after some of the roads we travelled on, I think it was just keeping us on the larger roads in the area and avoiding as much of the gravel paths as possible.