Typology http://www.typology.de is data structure for large amounts of text in order to suggest users next words they are about to type.

Typology was first developed by Paul Georg Wagner, Till Speicher and Rene Pickhardt (http://www.rene-pickhardt.de/tag/typology)

The code is available under an AGPL licence. This means that you can use this code free of charge as long as your built stuff that is also open source. If you want to be closed you will have to buy a commercial licence.

Typology can be used in Textprediction an significantly outperforms current state of the arte techniques like language models. It already won several awards which can be found at http://typology.de

It is also already available as an Android app in German language.