Email to your future self, or a sealed capsule?

How does an email to your future self work?

You write a message, pick a delivery date and a service sends it to an email address on that date. Some services are websites, some are apps, and some are features inside a mail client. The idea is the same: the message waits on a server and arrives in your inbox when the date comes.

It is simple and familiar, and you do not need to remember anything because the email finds you.

What are the weak points of scheduled email?

None of these is a reason to avoid email. They are reasons to match the tool to the message.

• The service holds your text in a form it can read, so privacy depends on its policy and security.
• The address must still work on the delivery date. People change providers, and old addresses get closed.
• The email may land in a spam folder or be buried in a busy inbox.
• Photos and audio attachments have size limits.
• The service has to exist on the date. Small ones close.

How does a sealed capsule differ?

A sealed capsule keeps the message on your device in encrypted form and delivers nothing. You open it yourself on the date. In Sealday the contents are encrypted with AES-256 on the phone, and the key is locked with the public drand beacon, which publishes the matching key on the open date. Before that the key does not exist, for you, for Sealday or for anyone else. See the time lock page.

The trade is that nothing is delivered. You need the app, or a backup, on the day. That is why the backup page matters more for capsules than for email.

When is email the right choice?

• A short, low-stakes note, such as a reminder for next spring.
• A message to someone else who already has the address.
• A note you want to find in an inbox without any effort.
• A purely practical memo.

When is a sealed capsule the right choice?

For a letter that waits a year or more, the guide to writing to your future self has prompts that work in both tools.

• Private writing, such as feelings, doubts and plans.
• Photos and a voice note that go with the letter.
• Guesses you want to grade honestly.
• Anything you would not like read by a service or a stranger.
• A message you will open in more than a couple of years, when addresses may have changed.

Can I use both?

Yes. Send yourself a plain email reminder on the open date: "Open your Sealday capsule today". The capsule holds the content and the email holds the date. It is a cheap second line of defense against forgetting.

Sealday can also remind you. If you allow notifications, it schedules one local reminder on the open date, without a push server. Reminders are optional, and you can switch each kind off under You > Reminders.

How do I write a message that works in either tool?

Start with the date and a detail from the room. Say what is going on, what you expect and what you want to ask. Skip anything that could hurt you if someone else read it, including passwords, account numbers and other people's secrets. That rule is good for email and still wise for a capsule.

Then pick the open date by how much you want to be surprised. A year is the usual first choice. Beyond ten years, a message in a sealed capsule with two backups is a safer bet than an inbox you may not have. If you have never done this before, try the one-minute version: one line to future you, a photo, and a hold on the seal.

What about apps that deliver letters?

Several iPhone apps deliver letters or notes at a date. They differ on sign-in, limits and how the lock works, so check each listing.