Some Notes On GPS Tracking on Android

April 16, 2015

Like everybody else, I have an Android phone too. If you are a developer you must have noticed a file called as GPS.LOG. It is the one file which has all your GPS logs in it. This weekend I spend couple of hours hacking with it. He is the outcome.

How you get tracked

First of all, connect your Android device to your computer and copy the gps.log file into your desktop:

cp /Volumes/NO\ NAME/GPS.LOG ~/projects/gps.log

Now, we need to find the good data that contain gps coordinates:

cat ~/projects/gps.log | grep 'position' > ~/cleangps.log

The cleangps.log file contains only data that has coordinates on it.

Now, create a log file that only contains coordinates:

cat ~/cleangps.log | awk '{print $3, $4}' > ~/gpscord.log
# notice the new file is nothing but values seperated by commas, hence write them as csv
cat ~/gpscord.log > ~/gps.csv

This csv file is the basis we use to find that location the GPS log was taken.

Prepare virtualenv and install googlemaps:

mkvirtualenv maps
pip install -U googlemaps

Also, follow the clear instructions at https://github.com/googlemaps/google-maps-services-python#api-keys to find your API key.

Here is the python file track.py that would find what these coordinate means and how they related to your daily life and place you are frequent to.

#! /usr/bin/python
import googlemaps
import csv

gmaps_client = googlemaps.Client(key='<Your Server Key Here>')

with open('~/gps.csv') as csvfile:
    gps = csv.reader(csvfile, delimiter=',')
    for row in gps:
        lat = float(row[0])
        longit = float(row[1])
        reverse_geocode_result = gmaps_client.reverse_geocode((lat, longit))
        formatted_address = reverse_geocode_result[0]['formatted_address']
        print row[0], row[1], formatted_address
        print "=" * 150

Run this file in your terminal by and check out the output, you will get freaked out for some moment.

python track.py