KeyboardKit
KeyboardKit is a Swift library that helps you build custom keyboard
.... It unlocks a bunch of pro features, like more locales, localized system keyboards, local and remote autocomplete etc. KeyboardKit comes with support for 50+ locales, with more being added over time. KeyboardKit has tools for customizing everything from keys, key behavior, layout, callout actions, audio & haptic feedback, colors and styling, autocomplete etc. The KeyboardKit app let you create keyboards directly on your iPhone and iPad.