FAQ

Why does a PDF open in another app?

Letos can preview only images and text files right inside the app. Other attachments — PDFs, Word documents, spreadsheets — are downloaded on the computer to a temporary folder and opened in the system’s default app (on a Mac, for example, Preview). On the iPhone they open in the system preview; in the web version they’re downloaded.

Why won’t Letos open an .exe or .app attachment?

For your safety, Letos doesn’t open executable files or scripts. It only shows them in Finder, and what you do with them is up to you.

Why do I need to allow notifications on the iPhone?

iOS only lets an app show notifications once you explicitly allow it. Once the setup wizard is done, Letos shows a Want to hear about new mail? card — the permission is requested when you tap Turn on, and Not now won’t bring the card back on this device. If you declined, turn notifications on in iOS Settings → Letos → Notifications. You can also see the state in Letos under Settings → Notifications → System permission.

Why didn’t I get an event reminder?

Check that Event reminders on this device is on for this device and that the system allows notifications. All-day and declined events have no reminder, and Letos doesn’t use reminders set in Google Calendar — your Remind about an event how many minutes ahead setting applies. On the computer, Letos has to be running.

What happens when I sign out?

On the computer and iPhone, tasks, mail, calendars, attachments and connected accounts (with their passwords) are deleted from that device. Nothing is deleted on the Letos server or at your mail provider — after signing in again everything is downloaded again. If something on the device hasn’t been sent yet, Letos warns you and offers to send it first. More in Sync and devices.

How do I switch between light and dark?

Settings → Appearance → Mode: Light, Dark or System (default, follows your computer’s or phone’s setting). The same section has Theme — the colour theme (the default is Letos). Appearance syncs across devices.

How do I change the app’s language?

On the computer, in Settings → Letos account → Language: Match system, Čeština or English. On the iPhone the language follows the system language.

Can I show another country’s holidays?

Yes. Settings → Display → Holidays and name days → Add a country… You can choose from the holidays of 244 countries for the years 2020–2040. Czech public holidays and name days are on by default only when the app is in Czech; name days are Czech only.

Do I need a Letos account?

Not on the computer or iPhone — Letos works without one; everything just stays on one device. You need an account for sync between devices and for the web version.

Can you see my e-mails?

No. Mail goes directly between your device and your provider. Our sync server only carries encrypted changes (tasks, triage state, settings) and can’t see their content. The exception is the web version: it runs on our server, so a web account’s data is stored there. Details in Privacy and security.

Do unfinished drafts sync?

No. Drafts stay on the device where you write them. Letos reminds you of them when you sign out.

I forgot my Letos account password. What now?

The app doesn’t have a self-service password reset yet. Write to [email protected]. After the password is changed, you get back to your encrypted data with the recovery code Letos showed you when sync was set up.

How many devices can I have?

It depends on your plan — see Pricing. Remove an old device in Settings → Letos account → Devices → Revoke access.

Does Letos support Outlook or iCloud?

You can connect iCloud, Outlook.com and other mailboxes over IMAP. Letos doesn’t have Microsoft sign-in (OAuth) yet, so Microsoft mailboxes may not work. For calendars, Letos supports only Google Calendar for now.

Is Letos available for Windows or Linux?

Not yet; they’re coming. The current state is on the Download page.

Does Letos send my data to AI?

Only if you turn AI on and choose a provider. The local model runs on your computer and sends nothing. For Claude, OpenAI, a CLI or a custom endpoint, Letos asks for your consent first and sends only the text AI is working on. More in AI.

Can an agent (MCP) send an e-mail on its own?

No. An agent can prepare a draft, but it can only be sent after you confirm it in the An agent wants to send an email window. With no answer within 120 seconds nothing is sent. An agent can’t delete anything at all. More in Agents and MCP.

How do I revoke an agent’s access?

In Settings → Agents click Generate a new token — the old one stops working immediately. Or turn off Allow agents (MCP) and the server stops.

Why doesn’t Letos understand “tomorrow” in a new task?

Quick add for tasks only understands Czech for now (“zítra”, “v pátek”, “příští týden”…). You can always pick the date by hand in the task detail.

Why can’t I add another yearly goal?

You can have at most five active goals. That’s on purpose — so your year has clear priorities. Park or finish one goal first.

Where do I find the log when something isn’t working?

Settings → Diagnostics → Open logs folder. Passwords and tokens are never written to the log, but it can contain e-mail addresses and subjects — check it before sending it to anyone.

How do I delete my account?

Settings → Letos account → More options (at the bottom) → Delete account. You first get an explanation of what happens, then you confirm with your password and by typing DELETE. Deletion is permanent and also deletes the local data on that device. Your mail at your provider stays.

How much does Letos cost?

Plans and prices are on the Pricing page.