Dave,, I think ,, you will find many urban folks will prefer smart phones to et als,,for city navigation and auto driving. Also for bicycle riders , smart phone is catching on,, and increasing use by motorcyclists as well, here in Korea.

I have augmented my G2 with following two cases,, one is a waterproof case, from buybit UK,
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which can be mounted on the handle bar and has sturdy locking structure as well as very thick inner rubber padding. In the demo,, I do see a biker using it, with riding gloves on.
The white one is another water proof bag that will actually float and can dive to 30 meters and camera can be used under water, which I use for sailing.

My recent trials between the Galaxy2 and Garmin ,, I find that smart phone locks into the satellite quicker and maintains the link longer than the Garmin. Where else ,, I keep getting signal lost or weak from my 755T.

As for Mapdroyd App ,, I find it rubbish ,, X blow outs not impressive at all. Rather using Locus ,, under Map ,, selct online map of your choice then Download ,, By Country ,, X 1,2 ,3 , 4 , 5, 6 , 7 and 8 gave me much clearer X blow outs. And with Vector Maps as a back up on my Locus for cities,, I can define the streets with maximum X blow outs. These you can use for OFFLINE ,, Even the online maps ,, including Google Map, Mapquest and OSM ,, if you cache the map, in significant quantity,,you browse on line ,, I find that I can carry x6 minimum on my phone for reference OFFLINE ,,

So , to download custom maps , you simply click few buttons in Locus,, rather than downloading OSM then using Mapsource to transfer to the et als.

But as I've said ,, like to put eggs in several baskets ,, will keep my Garmin, on the bike.

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