Tuntun is an iOS keyboard inspired by Minuum: a full keyboard compressed into a single line, about a third the height of the one you use now, so you keep seeing the app you're typing in. Flick right for space, left to delete a word, up for capitals, down for return; hold to zoom in on an exact letter. Named after escribir al tuntún - typing by feel.
To regenerate the language models from their public corpora, run
Tools/rebuild-models.sh (sources and licenses in ATTRIBUTION.md).