Small models, slightly improved, probably still not good enough for the same use as online models. Nothing wrong with incremental progress, however.
1.5B parameter model does seem to be a pretty decent step up, even beating larger models by a wide margin. I'm not sure why they didn't go larger -- having a more efficient model that fits on hardware the size of the RPi could be a gamechanger (IIRC TinyLlama 7B does run, barely).