[aprssig] Andorid APRS

[Stephen H. Smith]

On 12/23/2009 3:14 PM, Jeffrey Johnson wrote:
> This thread is discussing building an APRS application for Android
> (mobile phone) devices. I am particularly interested in interfacing
> between my radios (D7 and the like) and the android device for things
> like plotting positions from the radio on a map on the phone,
> recording them to a local database on the phone, as well as using the
> phones GPS to TX my position over the radio ... all in the absence of
> an internet connection (wifi, 3g or gprs) and also acting as an IGATE
> when an internet connection is present.  Essentially using the mobile
> phone as a 'smart' gps that can do many more things than a normal
> garmin gps or similar.
>
>    

1)     Android is a mobile phone operating system for smart phones 
developed by Google, that has been under development for several 
years.   A handful of devices available from several carriers now 
incorporate this OS. Perhaps the highest-profile device currently using 
Android is the supposed "iPhone killer" Motorola "Droid" smartphone 
being marketed in the U.S. by Verizon.

Although the base Android system is an open source offering that anyone 
can play with, cellular carriers are notorious for adding closed 
proprietary  extensions and disabling some features for marketing 
purposes; i.e. to drive you to an "App Store" to buy utilities to 
restore functions or add features supposedly proprietary to that network.

Currently technical press excitement is building over the imminent 
release of the Google "G-Phone", which would incorporate their Android 
OS,  early next year. Supposedly this device would be sold unlocked 
directly to the user, and would be potentially able to run on the 
carrier of your choice.   [However there is still the major divide of 
incompatible RF protocols/modulation techniques: CDMA (Sprint & Verizon) 
vs GSM (ATT & T-Moble) which presumably means there would have to be two 
"flavors" of such 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.



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.



3)     Android mapping apps are most likely to use Google Maps 
downloaded from the Internet via the cell phone's data access, meaning:

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. ]

b)     Once again, if you are out of the cell carrier's coverage foot 
print -- NO MAPS!!


> It appears that the easiest way to interface between a Radio and an
> Android device is via Bluetooth since lower level access to the USB
> stack is complicated or impossible without 'hacking' your phone.
>
> The end result would be an application for android devices that could
> work with several radios using a bluetooth to serial adapter like
> this. http://www.rovingnetworks.com/firefly.php
>
> On Wed, Dec 23, 2009 at 2:51 PM, Ralph Milnes<ralphmilnes at gmail.com>  wrote:
>    
>> For the less "bleeding edge" of us, could someone give us a layman's
>> description of what this is and how it might work with APRS?
>>
>> Ralph KC2RLM
>>
>>      

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Stephen H. Smith    wa8lmf (at) aol.com
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