• OpenTom software (current version: 0.0.3).
  • TomTom GO/300/500/700/ONE (only TomTom ONE version 1, the black one) PND. Technically, TomTom Rider is compatible but lacks a speaker.
  • An empty SD card (do you want to lose your maps ?).


First, download precompiled binaries (bottom of the page).
Unpack archive, and move the content to an empty SD card. The content to be moved is ttsystem file and opentom folder.
Into opemtom/media folder, put MP3 files you want to listen to.
Put the card into your PND, and switch it on. After a garbled statup welcome screen, you will be given access to the MP3 player interface. There are three tabs :

  • Clock : date and hour. It seems OpenTom does not use PND date and hour settings, so you'll have to setit up each time you use it. Use the Set button, Luke.
  • Music : all your MP3 on the SD card. From this tab, you will add file into the playlist (Add button), or change sound volume (Vol- and Vol+ buttons).
  • Player : The playlist itself. You may change files order. From this tab, you may start mp3 playing. Volume setting buttons are here again.
  • GPS : This tab shows data from GPS device. Unlike genuine TomTom software, elevation is displayed. I.e, I know I am 159m above sea level (you don't care, really !?).

You can see screenshots on OpenTom site.


The most important : OpenTom and genuine TomTom software are exclusives. You may use one of the other, but not at the same time. OpenTom only reads MP3 file, and have navigation features. If you want to use your PND navigation features, you may use it as a portable MP3 player (i.e. while driving). While walking, even if your PND has a jack connector, you can't set luminosity, then quickly empty the battery.


Size: OpemTom is only 5 MB on the card.
Elevation display is a good feature I would like to see on genuine TomTom software.


TomTom PNDs run Linux, then it's easy to create a replacement software, as OpenTom. Then I would like to see the following features:

  • Power management, with ability to switch screen of while playing music, or change processor speed on the fly.
  • Navigation features. I don't know if such free software exists, but a navigation feature which may use TomTom maps, or bitmap maps will be very good.