Calendar, tasks, and notes.
One surface, one assistant.
Tell Kelvin “lunch with Sam Tuesday at 1” and it’s on your calendar. One fast app for your whole day — with an assistant that actually does the work, not just chats back.
Say it once. Kelvin sorts it out.
One sentence in. A scheduled event and a tracked task out.
“Photo shoot Friday 2pm for work — remind me to charge batteries the night before.”
Photo shoot — Fri 2:00 PM
Charge camera batteries
Built for the whole day
Capture in plain language
Type or speak naturally — Kelvin pulls out the date, priority, and subtasks for you. No forms, no fiddling.
All your calendars, one view
Connect Google, iCloud, and Nextcloud. See everything together, and choose which calendar each new event lands on.
An assistant that acts
Ask it to schedule, reschedule, or check your week. It uses real tools to change your calendar and tasks — not just chat back.
Command bar, quick capture, even a vim-keyed calendar. Hands stay on the keys.
Speak to Ask Kelvin or quick capture — built on the browser, no extra cost.
Add to your home screen, works offline, talks to Siri through Shortcuts.
Your calendars connect with your own credentials, encrypted at rest. No mining, no resale.
Three moods, one app
Warm paper for daylight, slate for night — and a phosphor terminal theme for when you’re feeling it.
Getting in
Kelvin is in a closed beta on purpose — small batches, real feedback, fast iteration.
Join the waitlist
Drop your email below. We onboard in small batches so feedback actually gets acted on.
Get your invite
We email you a code when a spot opens. Locked-in pricing for life for waitlist members.
Bring your calendar
Sign in, connect Google / iCloud / Nextcloud (or skip it) — tasks and notes work instantly.
“Every productivity app I tried made me do their filing instead of mine — tag this, sort that, move it to the right list. I wanted one calm place that just understood a sentence and got out of the way. So I’m building it, in the open, with a small group of testers.”
— Tran, building Kelvin
Questions
Is it free?
Free during the closed beta. After launch it’ll be one simple low monthly plan — and waitlist members get locked-in pricing for life.
Which calendars work?
Google Calendar, Apple iCloud, and Nextcloud today, with more on the way. You connect with your own account; nothing is re-hosted.
Is my data private?
Your tasks and notes live in your own account, and calendars connect with your own credentials — encrypted at rest. We don’t sell or mine your data.
Does it work on my phone?
Yes — Kelvin is installable as an app on iOS and Android, works offline, and hooks into Siri via Apple Shortcuts.
When can I get in?
We’re onboarding testers in small batches so feedback actually gets acted on. Join the waitlist and we’ll email you an invite.
Have an invite code?
Enter it to sign in or create your account.
Get early access
Join the waitlist — we’re letting people in a few at a time, and early members keep beta pricing for life.