Draft instructions to use Iridium GO! for grib download and Routing


In order to make the most of your Iridium GO! and minimise costs I recommend using a combination of the following:

  • Iridium GO!
  • Screen copy program and USB cable phone to pc
  • Iridium email account
  • Iridium GO! App (not needed for routing)
  • Web Satellite Web Browsing (not needed for routing)
  • Iridium mail & Web app
  • qtVlm free open source routing software & Maps

Let’s go step by step.

Screen Copy

There are a variety of ways to screen cast your mobile to your pc but most rely on your wi-fi which you need to keep free to use your iridium GO! Using the USB cable has the added advantage that there will be no timelag between phone and pc.

Go to https://github.com/Genymobile/scrcpy and scroll down to “Get the App” paragraph and dowload the latest version for your operating system, e.g. for windows at the time of writing scrcpy-win64-v1.21.zip.

Extract the folder and install the application.

Connect your phone with the USB cable to your pc.

Search the program and launch it scrcpy.exe

If you see your phone screen on your laptop you are all set, try to see if mouse and keyboard work. If nothing happens see next.

Enable USB debugging mode on your phone

How you do this is different from phone to phone and you may want to search based on your make and model. On my Xiaomi Note 11 5g I had to go to Settings –> About Phone –> All Specs. Here i tapped about 8 times on the kernel version number and this activated the debug mode.

It is explained at this link:


In my case I had to tap on kernel number and not the build number.

Once you have done this, go back to settings and you will see a new Developer options which on my phone appeared under “Additional Settings”.

In developer options you have to turn on “USB Debugging” and “USB Debugging (Security Settings).

You can find additional resources here if you dont find your way around or have an iphone


After this step, relaunch scrcpy.exe and everything should work fine, if not, something has not been enabled in the steps above, for example without the “USB Debugging (Security Settings)” turned on you will see your screen but wont be able to interact with it from your laptop.

Apps for Iridium

Go to Play store and download “Iridium GO!”, “Iridium Mail & Web” and “xWeb Satellite Web Browsing” (optional). There are other apps you may be interested in.

Your Iridium email

Go to the Iridium Mail & Web Registration page and create an account, this will only be needed for the Mail and web app, not for the Iridium GO! app.

Your Iridium GO! Setup

Turn on your Iridium go, refer to the Iridium website instructions for more detailed information. Once the GO! has connected to the Iridium network go to your phone (screen casted on your pc or on the phone itself) and turn on aereoplane mode, deactivate bluetooth and look for the wi-fi named Iridium-XXXX and connect.

To test if everything is working so far, go to the Iridium GO! app and login as “guest” with password “guest”. Remember, the username and password you setup before for your email are NEVER needed here and won’t be recognised, always just login as guest.

To use of the app, making calls and sending messages please refer to the Iridium Website.

Iridium Mail and getting Grib files

The Mail and Web app offers you a Predict Wind and a Weather icons. We want to use Iridium GO with Saildocs which is the only system that provides absolute control over what you are downloading and allows you to tailor your file requests to receive small but useful files, the system was developed for SSB radios and I have not found any other system that allows the same level of control.

To request a grib file we will use the mail app.  Open Iridium Mail & Web and login with the details you used to create your account. Follow the steps until you see the home screen saying the system is idle.

To use Saildocs get the full instructions by sending an email with any/blank subject to info@saildocs.com, the system will automatically send you back the instructions.

In you Iridium Mail app now compose a new email and send it to query@saildocs.com with any/blank subject and specify your desired weather data. For example in the body of the email you could write:


You will notice that this requests will retrieve weather info every 3 hours for the first 12 hours, every 6 for the following 12, every 12 for the following 24 and every 24 for the following 24. In other words we request fewer snapshots the further away in time we are from now saving lots and lots of details which we are unlikely to need. Saildocs is the only sysytem that lets you play around so precisely with your request.

Use send and receive to send the email.

A few minutes later, go to send and receive again and you will have an email from saildocs with an attachment. It gives you the option to save it (to your phone), it will go in your download folder (exact address is given).

You are done as far as satcoms are concerned. So you can open the file explorer of your pc, where you can also see the phone memory, go to the download folder and copy the latest grib file to a “Gribs” folder created somewhere convenient.

Open Source Routing Sofwtware qtVlm

Download latest version of qtVlm on your laptop/tablet or mobile (through Play Store).

The Desktop version for Mac or Windows can be found here:

Once downloaded and installed you’ll be asked if you want to download maps, i recommend you do, they are basic land outlines, but more than sufficient for a circumnavigation.

Open qtVlm and select Grib –> Grib Slot 1 and open the file you had received from saildocs. It will display the grib on the screen which will also be available for routeing. qtVlm should be setup to received your current GPS position and other NMEA information as well as your polar files but we’ll discuss this in another set of instructions.