Cotypist 

Cotypist screenshot
Cotypist screenshot

Cotypist is one of the more interesting recent takes on system-wide text completion on the Mac, mostly because it appears to keep processing local and to use screenshot-derived context to improve what it suggests. That makes it potentially useful well beyond the usual “AI writing helper” niche, especially in situations where the surrounding UI matters as much as the current text field.

It also strikes me as a potentially valuable accessibility tool, since this kind of ambient completion can reduce typing effort, help with repetitive text entry, and provide a softer assistive layer across applications rather than inside a single editor.

It is currently free during the beta period, which lowers the barrier to giving it a try.