• You can add swipe (glide?) typing into HeliBoard. From their github readme:

    • Glide typing (only with closed source library ☹️)
      • library not included in the app, as there is no compatible open source library available
      • can be extracted from GApps packages (“swypelibs”), or downloaded here (click on the file and then “raw” or the tiny download button)

    The only reason HeliBoard doesn’t include this themselves is presumably legal liability plus their dedication to the app not having any network permissions at all.