On That Day: Time Capsule

On That Day is a private time capsule for the people you choose.

Add photos, videos, voice notes and letters today. Seal them. They stay hidden — from everyone, including you — until the day you picked. Then the capsule opens, and you all see it together for the first time.

WHAT IT'S FOR
A first birthday to open at eighteen. A wedding capsule your guests fill on the night. A year of small things for someone far away. A letter for an anniversary. Anything worth waiting for.

HOW IT WORKS
1. Create a capsule and pick the day it opens.
2. Invite the people who should be in it. They add memories from their own phones.
3. Look through everything before the day, and decide what goes in.
4. On that day, it opens for everyone at once.

END-TO-END ENCRYPTED
Photos, videos, voice notes and text are encrypted on your device before they are uploaded. We store ciphertext. We cannot read your memories, and neither can anyone you haven't invited. Your keys are protected by a recovery phrase you control.

MEMORIES
• Photos — one at a time or a whole batch, with captions, dates, locations and the people in them
• Video — up to 30 seconds, recorded in the app or picked from your library
• Voice notes — say it instead of typing it
• Letters — written on real stationery

TOGETHER, NOT ALONE
Invite someone and choose what they can do: run the capsule alongside you, add their own memories without seeing anyone else's until the day, or simply be there when it opens. Every capsule has a People screen — who's in, who's waiting to be let in, what each person can do — and a record of what happened in it.

BEFORE IT OPENS
Nothing goes in unseen. Before the reveal, owners look through every memory and sign off on it — or leave it out. Memories you mark as a surprise stay sealed even from the other owners.

PRIVATE BY DESIGN
• No ads, no trackers, no third-party analytics or crash-reporting SDKs
• Nothing is written to your Photos library unless you ask for it
• Delete your account from inside the app, and choose what happens to the memories you shared

SIX LANGUAGES
English, Turkish, German, Dutch, Spanish and French — the whole app, including the permission prompts.

Free to use.