Thursday, June 16, 2016

MRA Mapping Hangout #5 - Snap2Map

This month we had some audio issues with our Google Hangout, but I did go back and record my Snap2Map Demonstration embedded below. 

Snap2Map is a really simple way to make a map with interactive geo-tagged photos. This can be used for a wide variety of applications. For SAR the use-case we are exploring with the YSAR Tauranga is using the Map Tour to create SAR PrePlans. A Map Tour could include photos and videos to highlight:
  • Hazards in an area 
  • Landing zones for helicopters 
  • Missing "decision points" on a trail
  • Any intelligence that you would like to capture with a map and photo!

Here is the free Snap2Map Tutorial by Jennifer Lentz if you would like to get started. It walks you through the following steps. 
  1. setting up and logging into an ArcGIS Online (AGOL) account
  2. downloading Esri's free Snap2Map app (available for free on Android and Apple-based smart devices)
  3. downloading a GPS tracking app (optional)
  4. Connecting your Snap2Map app to your organization's AGOL account
  5. Selecting the geo-tagged photos you'd like included in your story map, and publishing them to the story map through the Snap2Map app
  6. Editing your story map on a computer, including changing the basemap, color scheme, etc.
  7. saving the story map
  8. editing the information provided in the "details" page of the Web Map, including change the thumbnail image, and sharing preferences
  9. adding tracking data to your story map (optional)
  10. viewing the finished Story Map 

Thank you to YSAR Tauranga for the inspiration - I look forward to seeing your end product and seeing if any Mountain Rescue Association Teams pick this up and try it out. 

Wednesday, June 1, 2016

Cell Phones and SAR - Browser-based Location Apps

This article is a quick summary of a browser-based location applications that have been discussed on the Using GIS in SAR Discussion Group

Example Cell Phone Forensics Decision Tree, George Durkee - Operational Guide

These are free apps that can be used to locate persons that need help, are responsive, and can access the network - even with a fairly limited connection (using SMS).  It is a good idea to get familiar with all four as they can be used in different circumstances.

CellGPS (Eric Menendez @ericrmenendez)

Cellular device geolocation web app powered by Twilio, also on GitHub cell-gps. This app is very simple. It basically sends a text message to a cell phone, requests to activate GPS, then sends maps of coordinates of SMS reply. Try it!
  1. A SAR Team member should login from a PC browser (as a Guest) at 
  2. Enter a phone number and short message. Once the person receives the text message and clicks on the link - the coordinates and accuracy will be sent to the admin console.
  3. Go the admin console and click on the coordinates under the Location column. 

FindMeSAR (Joseph Elfelt @MappingSupport)

"Any 911 dispatcher can ask a wireless caller to browse to "", open that web page and soon read off their coordinates usually with a 10 meter or better location accuracy."

The person who needs help has to be told by voice or text to browse to and might need to give permission for their browser or the app to use location services.  If the user cannot get online with their browser, then the app will not work.

The “Next format” button cycles through four coordinate formats including USNG (same as MGRS).  Each coordinate format has a different colored screen.

The app continuously asks the API for the user’s location.  The first location displayed will likely have a high accuracy.  If the user is outside or even next to a window, then in well under a minute the accuracy value will usually be 10 meters or less.

The person who needs help has to read or text the coordinates and accuracy to whoever is receiving their information.

There is more documentation at: (Michael Coyle @Michael_F_Coyle)

"Free" mode: users can go to the web site, and generate an URL. You text the URL to the lost person. The web page loads, determines the location, and sends you the location via email.

"Advanced" mode:
  • Agency signs in and creates a new request. Form auto-fills details and includes a field to reference a unique ID for the request.
  • Agency sends text to subject via the web (back end is Twilio)
  • Agency monitors the request on the monitor page
  • When subject loads the web page, location is "pushed" to the monitoring page. 
    •    Location displays on google maps
    •    Page "pings"
    •    Estimated error displayed
    •    Coordinates in Lat/Lon and UTM
    •    Can download GPX / KML
  • Send and receive SMS with subjects
  • SMS log with subjects


"SARLOC has been around since 2011. It has been used by many teams around the world but is mainly used in the UK.

In the UK we use a program called MRMap ( to track team members radios which have a GPS in the handset. Each radio has a unique ID."

SARLOC uses the web browsers geolocation API to attempt to get the phones position.

SARLOC can be activated in three ways.

  1. The team send a link to the LostPer with a radio ID as a parameter. When the user clicks on the link, the radio ID gets added to an online database with its location and it appears on the MRMap screen
  2. MRMap can make a web call to SARLOC passing in a radio ID. SARLOC then generate a unique token and sends an SMS to the LostPer. When SARLOC gets the position back, it retrieves the radio ID associated with the unique token and adds it to the online database when MRMap can display it from.
  3. Where the MRT does not have internet access, the team can send an SMS to a virtual ‘phone number provided by the SMS gateway provider (In our case this is WorldText) The provider calls a SARLOC URL and SARLOC sends the SMS to the LostPer. When SARLOC gets the position it sends it back to the MRT as a text message. therefore they do not need internet access.

Russ Hore has a worldwide version you can test with.

The LostPer needs to click on the following URL;

After the MYID= the MRT need to add something unique to them such as PaulDoherty_2016_06_01

When the LostPer click on the link, the location can be seen at;

Fixes at this URL are removed after 72 hours. To see historical hits use;

Having Trouble? 

If you run into any issues, consider the device's browser settings (Help for Chrome / Android and Safari / Apple). 

Remember these are not "apps" you download onto your PC or Mobile Device, they are websites with special capabilities. Therefore, bookmark or add shortcuts to your home screen.

Key Message

(By Joseph Elfelt)

"It is likely that no one app will always be best suited for all circumstances.  I invite everyone to take a look at these apps and get a sense for what they do and how they do it.  Then when a SAR mission comes along you will be able to make a well-informed choice as to whether any of these apps will be helpful.

All three apps use the same browser geolocation API.  That API uses the cell phone’s location services to obtain (1) latitude longitude coordinates in decimal degrees and (2) accuracy in meters.  If you draw a circle at the coordinate and use the accuracy value for the radius then the specification says there is supposed to be a 95% likelihood that the cell phone is inside that circle." 

For documentation on that API see:

Cell Phone Forensic Workflows for SAR
Finally, George Durkee of Columbia College have put together the "Operational Guide to Cell Phones for SAR" a living document that should be extremely helpful for SAR Teams in the coming months.