It is possible to use custom navigation voices in the Navigation function. This method shows how to convert voice files from TomTom application to the format usable by Locus Map.

Firstly, you need to have some TomTom voice file. One usable site with a lot of free voices is for example here >>.

• at first, prepare necessary material - voice data and Viftool software
  • download a voice template and save it to some a new folder (e.g. C:\my_tomtom_voice). You need to save these 3 voice related files: VIF, CHK and BMP file.
  • download VIFTOOL
  • install downloaded Viftool to the folder with the voice template.
  • go to Start > Run > CMD
  • type cd c:\viftool\ in the command window
  • then type viftool.exe split dataXX.chk to extract all ogg voice files from tomtom CHK file.
  • this way you’ll get directory full of *.ogg files. And now simply pack all these .ogg files into one .zip file (only files, not whole directory).

• as a result you have four files:
  • dataXX.bmp - image (optional)
  • dataXX.chk - original voices (not needed)
  • dataXX.vif - description file (required)
  • dataXX.zip - voices (required)

Copy *.VIF and *.ZIP (you can also *.BMP) files directly into Locus/data/nav_audio directory in your phone.