Grammarly vs Typeahead

Option A

Grammarly

Last-mile grammar, tone, and clarity in the text boxes where writing actually happens.

Best for

• Daily polish across many apps
• Non-native English writers
• External-facing channels first

Strengths

• Ubiquitous
• Low friction

Trade-offs

• Over-corrects
• Not a strategist

Verdict

Grammarly is the last mile. ChatGPT and Claude generate. Clearscope grades. DeepL translates. Typeahead completes on-device. Roll it out on customer-facing surfaces first. Tell people they may reject tone. Confirm the business plan if you need admin. If fiction is the job, turn it down or off. Roll Grammarly out on external channels first. Turn it down for fiction. Pair with ChatGPT for generation and DeepL for translation. Confirm admin if you need it. If the team writes in one app with its own checker, do not stack nags without a reason.

Option B

Typeahead

On-device sentence completion for every Mac text field. Drafts stay on the machine.

Best for

• Mac writers who live in native text fields all day
• People who refuse to send drafts to a cloud model
• Ghost-text fans who already like IDE autocomplete

Strengths

• Private by construction, not by a settings toggle
• Latency feels like the OS, not like an API
• One job, finished

Trade-offs

• Mac only
• Will not become your editor or inbox

Verdict

Typeahead should be on the shortlist only if the problem is “finish this sentence in the field I am already in,” and the constraint is that the keystrokes cannot leave the machine. That is a real, narrow job. It is not a Notion replacement, not an inbox, and not a writing coach. Superhuman still wins if the unit of work is an email thread. Grammarly still wins if the unit of work is a grammar pass across browsers. Notion AI still wins if the draft has to live next to the rest of the wiki. Buy Typeahead when those products feel like too much surface area for a caret that just needs a next-token guess — and confirm the Mac-only license before you pitch it to a mixed-OS team.