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[aprssig] Andorid APRS

Stephen H. Smith wa8lmf2 at aol.com
Thu Dec 24 01:32:09 UTC 2009


On 12/23/2009 4:38 PM, Jeffrey Johnson wrote:
>
>
>    
>> a phone.]  The real question now is which (if any) carriers will allow a
>> non-proprietary non-crippled version of a "generic" phone operate on their
>> networks.
>>      
> I have various unlocked phones including Nokias and the Google Dev
> Phone. Unlocked means just that. I can put in a SIM from any (GSM)
> carrier I like and it 'just works'. There is the issue of incompatible
> 3G frequencies between the carriers. If you have ever travelled in
> Europe or anywhere else in the world that uses GSM (pretty much
> everywhere), the paradigm of unlocked phones predominates. Its only in
> the US that we have the paradigm of phones locked to a specific
> carrier.
>
>    

Exactly.   How likely are networks like ATT and T-Mobile to sell you a 
SIM for a phone that not "theirs"?   [I'm well aware that this issue of 
carrier "lock-in" is far less of an issue outside the U.S.]

And what do you do about CDMA networks that don't use SIMs???  Beg for 
mercy from Verizon or Sprint?



>> 2)     Most cell phone GPS's are relatively dumb devices (just the RF front
>> end) and depend on cell network access to function. As a result, your APRS
>> GPS functionality would disappear when you leave the coverage footprint of
>> your chosen cell carrier, if you try to use the phone's GPS with your radio.
>>      
> You are talking about Assisted GPS here. Yes this is very true of lots
> of what I would call 'low-end' smartphones (blackberry, windows mobile
> etc). This is simply NOT the case with Android devices or iPhone. The
> GPS in my G1 and my iPhone works just fine if I turn off ALL of the
> radios.
>
>    




>> 3)     Android mapping apps are most likely to use Google Maps downloaded
>> from the Internet via the cell phone's data access, meaning:
>>      
> Google Maps is one of many options available to android developers. I
> have developed android apps based on OpenStreetMap, maps I have
> created myself with open source tools using the Nutiteq library among
> others.
>
>    

I have found the quality and accuracy of the OpenStreetMap maps to be 
rather underwhelming.

Is there anything that can/could be loaded locally onto such a device 
with a comprehensiveness similar to MapPoint, Delorme Street Atlas, or 
the NavTeq database used by Garmin GPSs that would provide an up-to-date 
seamless street-level map of all of North America?

I.e.  produce an experience similar to UIview with Precision Mapping  or 
APRSpoint using MS MapPoint running on a laptop, without having to 
endlessly download additional snippets of maps as you travel across the 
US or Canada?

[All three of these mapping systems cover all of North America down to 
street level with numerous other outline overlays (parks, hydrographic 
features, campuses, malls, National Parks, military bases, etc) and 
millions of point objects of interest in a total file size of about 1.5 GB.]

>> a)   You are potentially going to run up huge airtime charges for data
>> acccess.  Most so-called unlimited data plans have monthly bandwidth caps;
>> i.e. download quotas of "x" megabytes.  [Currently the iPhone users tethered
>> to ATT's network are screaming and howling about ATT's plan to do away with
>> unlimited data access and start charging by the amount of monthly bandwidth
>> used. ]
>>      
> Monthly bandwidth caps on Verizon and other carriers are measured in
> the Gigabytes of data which constrains usage like video and audio
> streaming. AT&T currently does not have bandwidth caps, but is
> considering going to tiered pricing.

It seems to me to be obvious that as the number of data-gobbling 
non-voice gadgets (especially Web browsers) on wireless networks 
explodes (as ATT is now experiencing with the hordes of iPhone users),  
that flat rate (or quasi flat rate) plans will go by the wayside.

Further, when devices have "real" web browsers that can view normal 
"uncut" webpages like a normal PC (such as the iPhone can), even 
gigabytes of bandwidth/month go fast,  if you do much web browsing at 
all, given the ever-increasing bloat of inefficiently-coded web pages 
loaded with meaningless graphics, Java applets, Flash animations,etc.


> In any case, maps are actually
> quite small in size. unless you want to cache a huge chunk of maps
> down to your phone in which case, you could use an android based
> device like the Archos 5 Internet tablet
> http://www.archos.com/products/imt/archos_5it/index.html?country=ru&lang=en
> which is WiFi only and doesnt even work on the cell phone networks.
>    

Hmm....   Looks conceptually somewhat like an iPod Touch; i.e. an iPhone 
without the phone.     Tying a device like this to an APRS radio would 
be essentially the same as tying any other laptop or netbook to an APRS 
radio, except that you would be re-inventing the wheel creating an APRS 
app for a different operating system.     I was assuming the whole point 
of an Android-enabled application WAS to use it on a cell-phone-type 
device that could use wireless networks with longer range than WiFi.

>    
>> b)     Once again, if you are out of the cell carrier's coverage foot print
>> -- NO MAPS!!
>>      
> There are a plethora of apps for the iPhone that allow you to download
> maps to your phone while on a WiFi connection and then use them out in
> the field without an internet connection. Many/Most of these are based
> on the Route-Me library which can be used with various map tile
> sources including OpenStreetMap, Bing (Microsoft Maps), Yahoo Maps and
> even google maps if you don't mind violating the Terms of Service. I
> have also developed several apps based on this library and have been
> able to use my phone with GPS AND Maps in the absence of cell coverage
> or WiFi.
>
>    
Again, how much space would it take to cache/store/archive (whatever you 
want to call it) coverage of the entire US?   Would most devices have 
the local storage available to do this?      [I ask since I was shocked 
to see the immense size of the full US database for the U.S Government 
"Tiger Files" map database for example, compared to commercial products 
like Street Atlas, MapPoint, etc.]

Note that I am thinking in terms of smoothly-zoomable/scrollable 
vector-based mapping, not tiled arrays of bitmaps that have to be stored 
repeatedly at different resolutions.



------------------------------------------------------------------------

--

Stephen H. Smith    wa8lmf (at) aol.com
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