The vustat apps are available in thirteen languages
You can force a language by giving it a parameter. For example to start the sampling app in Dutch by adding www.vustat.eu/apps/index.html?
A special app is made to edit a multi-lingual app. All the json files can be made multi-lingual, although the json-file for data analysis are different. The app www.vusoft.eu/apps/googledata allows to edit the words in the app.This app makes it possible to edit the info-information. With this app you can edit the json file directly. This is very tricky. If you do this you should check if it is valid json file after your changes. Please check this with a json validator like http://jsonlint.com/
The files associated with data analysis are treated different. See the post