Automobile GPS that shows One-Way Streets

[WillTheGISGuy]

Howdy,
I've had numerous automobile Garmin GPS units that I use as a part of my vehicle data gathering work. I need to drive down many streets everyday and often run into one-way streets. Garmin units seem to know that I am going down a one-way street (they scream blood murder as I start to go down the street), but they don't show streets as one way on the maps. It would help me plan routes and just navigate more effectively if I could see which streets are one way before I get to the streets. Does anyone know of an automobile GPS that shows direction arrows for one-way streets? I have researched the Garmin units for this, but no luck. I see that Google maps shows that and Open Street Map as well, but I can only get those on my phone and I am often out of 4G cell range.
Any ideas would be greatly appreciated.

Thanks, Will.

 

[Nuvi-Nebie]

The problem here is that Satnav makers make a decision as to what is displayed on the screen, through a process called rendering, even if the map makers have included one-way information in their maps it may be discarded before the map is sent to the satnav, even when it is sent to the satnav it may have been 'turned off' for display purposes, this is done because of limited processing power in the satnav and the need to draw the map very quickly

The only way around this I have found is to use an App. such as OSMAnd on a Smartphone, as you say OSM maps have one-way information, however OSM maps when downloaded to a Garmin Satnav don't show one-way roads, but they do on a Smartphone, you don't need a cell phone signal to use OSMAnd because the maps are help on the Smartphone, so you only need a GPS satellite signal, here is a screen dump of an Android Phone running OSMAnd showing one-way streets

 

[WillTheGISGuy]

Thanks for the tips. I understand the need for paring down what is displayed due to limited processing power especially when the map is refreshed every second or so. I am a GIS programmer, but for desktop apps, not mobile. And so far, I don't code for a rotating display and in a 3D (2.5D) driver perspective. Yes, I am spoiled having those features. OSMAnd looks like a great option. Lots of features, but my phone isn't really big enough for decent display. I could put it on a 7" tablet that has a GPS, but so far I can't see options for a 3D driver perspective and rotating display.
However, I may have found what I need. Although nothing pops up what I google for "Stanavs that show one-way streets", it occurred to me that commercial truckers would need that feature even more than I would. When I looked into the commercial trucking satnavs (expensive), I found that the Rand McNally OverDryve and TND series satnavs show one-way streets. Not very prominently, but it's more than I get with the Garmin units.

Thanks, Will.