There is a bit of a tension between ham radio and Cellular phones.  It's true - cell phones have eaten a fair amount of Amateur radios' lunch and that is not likely to cease any time soon.
Still, Ham Radio propeller heads and smart phone propeller heads tend to overlap somewhat, and although smart phones don't operate in the ham bands, that doesn't mean you can't have tons of ham-radio related fun with them.  The cost of these applications vary and are typically between 0 and $10 and many are available on both Android and iPhone devices.  With the right apps your smart phone is a very useful tool to the ham radio operator.  Below are some of the tools I have found and use. 
Echolink :   Most everyone knows that Echolink uses internet technology to connect you to a remote radio repeater.   What you may not know is that common smart phones can now run Echolink directly - without a computer.   This in effect turns your phone into a usable two-way radio connected to any Echolink repeater.   With your 3G service, you may use Echolink whereever you are.  
Voxer:   Voxer is an application that turns a smartphone into a two-way radio - one that (unless configured otherwise) automatically logs the GPS location of each party in the conversation and the time each message was sent.   Repeating an incoming message is as easy as touching the message you want to hear again.  Voxer uses wi-fi or 3G connectivity to send the messages, so participants need not be near each other.  Messages can be to individuals or to groups.  Voxer also allows participants to send camera images in the messages.
CWSpeed:   CW speed is a CW tutor that sends messages in Morse Code for you to copy.   It keeps track of your success rate and adds new letters as accuracy improves.  
Satellite Ham Radio:   Satellite Ham Radio is tells you when ham radio satellites are above your location, what bearing they are from you, and what frequency and mode they operate on.
MyRadar Weather:   This app gives you a nice weather radar image from the National Weather Service along with an indication of your precise location.   An add-on also adds the capability of showing NWS or other government alerts open for your area.
Morse Defender:   This gets the prize for the most innovative of the bunch.  Imagine a game like Missile Command - but with a Morse code twist.  Each landing projectile has a letter, number, or symbol.  To fire at an incoming projectile you must "send" that letter's Morse code by touching the screen in its dot-dash pattern.
MorseKey:   Morse key is the digital equivalent of a code-key practice oscillator.  It can be either straight-key or Iambic.
Freq Finder:   This app is a "smart" repeater directory.   It is location aware, so you set the band(s) and the distance you want, and it will tell you which repeaters are within that range and what their tones/offsets are.  It will filter out entries that are beyond the distance or not in the bands you specify.
iBCNU:  iBCNU makes your smart phone part of the APRS network.   It will beacon your location using the phone's GPS and Internet connection, but will be visible and usable with normal RF aprs connections as well.   It supports instant messaging using the APRS protocol as well.
5-0 radio:   This app is a practical substitute for a digital trunking scanner.   It provides a means of monitoring of public service frequencies by streaming the audio through an internet connection.
Maidenhead:   This app wil give you your precise grid-square location based on the GPS receive
Callbook:  This app will look up the callsign you specify on a varity of sites and return the public information on the callsign.
While I have not found a great app for Amatur Band plans, I have found it very useful to dowload these as PDF files that can be viewed on a smartphone. Have any other apps that you think other ham radio participants would be interested in?   Email them to Tim Neu  This email address is being protected from spambots. You need JavaScript enabled to view it..

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