Using an external USB GPS with Android devices (or Laptops)

The very first post on this blog Using an external bluetooth GPS with Android device is creating quite a bit of traction for my blog lately. This may be because not a lot of stuff on the Internet with appropriate keywords is available on the subject. This realization makes me write this post. What if you have a USB GPS instead? I am going to share my experience here.

Assuming that you have a USB GPS which can spit NMEA sentences (most of them do, as I know of), you can connect it to your Laptop through a standard USB port and use an appropriate software to collect location and other information from the GPS, or start logging data in a file for later use. I shall cover that in a later post.

What if you don't have a USB GPS already, and may be planning to have one? Well, go for it. Generally they come in two shapes: in a USB stick like your flash memory stick; and in a mouse-like appearance - GPS chip in a case connected to a long cable to USB port. Mine is of latter type, I bought it from Amazon (UK) for about 30 GBP, it looks likes this. Here is a picture of mine (with an OTG cable lying around).

Now that you have to connect the GPS with your Android tablet or Smartphone, you don't have a standard USB port on your device. What you will need is a small piece of hardware called OTG (on-the-go) cable. Here is an example on Amazon. This is a small cable with a micro-USB male interface on one end which plugs in to your Android device, and a standard USB female port on the other end to plug in any USB device, including your GPS - like I show in this picture.

Now that your hardware side is ready, you will need an appropriate App to communicate with the GPS. In the past I have used several Apps, e.g. USB GPS, USB Terminal etc., but lately I have come across a new and simple App which I would recommend for the purpose. It is called You Are Here GPS. To be able to use GPS signals with your other favorite map software, enable mock locations in Android Settings > Developer Options - as seen in this screenshot.

Now run You Are Here GPS and tap 'Connect'. You will start to see NMEA sentences appearing in the terminal. This app doesn't have a long list of settings, just the serial baud rate option. If nothing appears, or appears wrong on the screen, try changing the baud rate. Now send this running app to background without killing it, and open your favorite map software to receive data from USB GPS.

Using an external Bluetooth GPS with Android Device

Some Android phones (and other smart-phones too) come with built-in GPS receiver (in addition to AGPS capability, that means it can acquire location from GPS satellites like a standard handheld GPS receiver), but many of them are not as fast and as sensitive as a dedicated GPS unit in acquiring satellite signals and getting a fix (location). They are generally very slow in getting the first location fix (mine takes 30-40 minutes to get a fix when I am standing still, and takes eternity when on move). This is frustrating and virtually makes the phone's GPS a useless piece of hardware. High battery drainage is another compelling reason for not using the phone's GPS. Some smart-phones doesn't have built-in GPS. This is where an external bluetooth GPS unit fits perfectly. These external GPS units with no display, a built-in rechargeable battery, a few LED indicators and a bluetooth radio are generally pretty small and lightweight. These have a much better GPS circuitry than most smartphones on the market do, while they cost between 50 and 100 USD.

Mine is a Freedom Keychain GPS 2000 bought from amazon.co.uk for about 40 GBP. Here is a picture of the unit-

This unit and other similar product come with a home and a car charger, needs a couple of hours for charging, and runs for a good 10 hours. Mine also goes to sleep when no bluetooth device is using the unit to conserve power elongating the effective run-time.

How to use with an Android smartphone/tablet:

1) Switch on the GPS unit and Enable Bluetooth on your Android device. You can 'discover' the Keychain GPS on the Android's available bluetooth devices, as shown in the following picture.



2) Pair and connect the GPS unit from Android device. Usually the pairing code is 0000 or 1234. Mine's is 0000.



3) Download one of several Android Apps from Google Play (former Android Market). My favorite is Bluetooth GPS, good alternatives can be Bluetooth GPS Provider and Bluetooth GPS Provider (yes, the same name, but two different apps). However, don't confuse with the app Bluetooth GPS Output, which is for making your phone an external bluetooth GPS to be used on other devices. These apps will actually provide a port to the external GPS, that means they make the satellite signals from the external GPS used on your phone in such a way that as if the signals are being received by your phone's built in GPS. This lets you use other map Apps such as Orux, Locus, Google Earth, Google Maps etc while the port App is running in the background.

4) Run the Bluetooth GPS. Here is how the App's main screen look like. NOTE that the app has four tabs: Main, Status, NMEA, and Map. If the Keychain GPS is paied over bluetooth, you should see the GPS appearing in the drop-down device list. Select the GPs and hit 'Connect'.

To be able to use the external GPS's data in other Apps, you must check "Enable Mock GPS Provider" before hitting 'Connect'.




5) If everything goes well, you should see time, location and other GPS information being updated on this screen. If you still don't have a location fix, because you are indoors or for other reasons, you can still check if the GPS is working properly on your Android device. Swipe to go to the NMEA tab, and hit 'View log' (it becomes 'Pause' after you hit it). You should see the GPS's NMEA data sentences appearing endlessly on this screen.



6) Now, don't quit or kill the Bluetooth GPS app, just send it to background while it is still running. Open your favorite map App, or any other location aware App to receive location information from the external Bluetooth GPS.