Menu bar popover
See the last 5 actions and what was recognized, with Undo, without opening the window.
File autopilot for macOS 26
New files land. Letterslot files them.
Letterslot watches Downloads and Desktop, reads each new file on your Mac and renames, moves, tags or trashes it by your rules. Every step lands in the journal, with Undo.
14 days of everything free, then free for good with 2 rules, or Pro for €24 once. No account.
The AI features need a Mac with Apple silicon and Apple Intelligence turned on. Without them, rules by name, type, age, size and text keep working.
Rechnung_2026_000123.pdf~/Downloads
two seconds later
2026-10-12 Nordlicht Hosting 12,34 EUR.pdf~/Documents/Belege/2026/10
recognizedInvoice · Nordlicht Hosting · 12,34 EUR · Oct 12, 2026Undo
[PLATZHALTER] Video des Zehn-Sekunden-Moments (WebM und MP4)
How it works
Watch, read, understand, file.
1Watch
Letterslot watches the folders you pick, usually Downloads and Desktop, and waits until a file has finished downloading.
2Read
It reads PDF text directly and uses Apple's text recognition for scans and photos. All on your Mac.
3Understand
Apple's on-device language model tells it what the file is: kind, sender, date, amount. Amounts and dates are cross-checked with fixed patterns.
4File
Your rules rename, move, tag or trash it. If anything is unsure, the file waits as “Please check” instead of being filed wrongly.
Features
Rules you can read. Actions you can undo.
Describe a rule in one sentence
Type what should happen, for example “invoices from Downloads to Documents/Invoices by month”. Letterslot turns it into a rule and shows it as a sentence and a form. It never runs until you accept it.
- Conditions: kind, sender, date, amount, file type, name, age, size, text
- Actions: rename, move, copy, tag, open with, to the Trash after N days
- Templates for receipts, screenshots, installers, contracts and bank statements
A dry run before anything moves
Before a rule runs, see what it would do with the newest 50 files in the folder: old name, new name, new place. Change the rule until the list looks right.
- Name templates with date, year, month, sender, amount, currency, kind, title
- Safe names: no clashes, no forbidden characters
- Files the app just moved never trigger it again
A journal with Undo for every action
Every rename, move and tag is listed with the old and new place. Undo moves the file back and removes the tags. The menu bar popover shows the last 5 actions.
- “Please check” filter for unsure recognitions
- AI results are labeled “recognized” and can be corrected
- Never deletes permanently, only moves to the Trash
Receipts per month, ready to hand over
The receipts page lists every invoice and receipt of a month with sums per currency. Export a ZIP with all PDFs and a CSV list (semicolon, UTF-8 with BOM, German number format) for your spreadsheet or your tax advisor.
- Values can be checked and corrected
- Not tax advice, no promise that receipts are complete
- Recognized on your Mac, please check
Command palette
Press ⌘K to search every rule, folder and action, for example “clean up now”.
Shortcuts
Three actions: Clean up folder now, Recognize file, Export receipts for month.
Compared with Hazel
Hazel matches patterns. Letterslot also understands content.
| Hazel | Letterslot | |
|---|---|---|
| Rules by | Name, type, dates, size, text with patterns | Name, type, age, size, text |
| Content | Text and patterns you define | Also kind, sender, date and amount, recognized on your Mac |
| New rules | Rule editor | Rule editor, or one sentence turned into a rule you check first |
| Price | $42 one-time | Free tier, Pro €24 one-time |
| System | Also older macOS versions | macOS 26 or later, AI needs Apple silicon and Apple Intelligence |
Hazel has more actions and years of polish. If your Hazel rules work, keep them. Hazel details from Noodlesoft's public information, as of November 2026.
Privacy
Your files stay on your Mac.
Read on your Mac
Files, their text and everything Letterslot recognizes stay on your Mac. No account, no telemetry, no cloud AI.
Apple's model, locally
Understanding uses Apple's on-device language model (Foundation Models, part of Apple Intelligence). It runs on your Mac, offline.
Two connections, both named
Dodo Payments for the license check (key and device name) and this website for the update check. That's all.
Pricing
Free to keep. Pro once.
14 days of everything free. No account, no card.
Pro
€24 one-time
- Unlimited rules and folders
- Rules from a sentence
- Receipts export (ZIP + CSV)
- Shortcuts actions
- “After N days” actions
- 2 Macs, all 1.x updates
Prices include tax. [PLATZHALTER: Steuerhinweis zum Preis] Sold by Dodo Payments as merchant of record. 14-day right of withdrawal, even after download: details · license terms
FAQ
Questions, answered.
Does a file leave my Mac?
No. Letterslot reads your files, the text in scans and photos, and everything it recognizes on your Mac. Text recognition uses Apple's Vision framework, understanding uses Apple's on-device language model (part of Apple Intelligence). Letterslot uses no cloud AI. The app only connects to Dodo Payments to check your license key (key and device name) and to this website to look for updates.
What if I don't have Apple Intelligence?
Then the AI conditions (kind, sender, date, amount) and rules from a sentence are not available, and the app says so clearly. Rules by name, file type, age, size and text keep working, much like Hazel. The AI features need a Mac with Apple silicon, macOS 26 or later and Apple Intelligence turned on in System Settings.
What if the AI is wrong?
Every recognition is labeled “recognized” and can be corrected. Amounts and dates are also read with fixed patterns. If the model and the patterns disagree, or the model is unsure, the file is not filed: it waits in the journal under “Please check” and you get a notification. Every action can be undone.
How is it different from Hazel?
Hazel (Noodlesoft, $42) is a mature tool that matches files by name, dates and text patterns. Letterslot also understands what a document is: an invoice from Nordlicht Hosting over 12,34 EUR, not just a PDF with a number in it. You can describe a rule in one sentence and check it before it runs. Hazel has more actions and runs on older macOS versions. If your Hazel rules work, there is no need to switch.
How do I undo an action?
Open the journal or the menu bar popover and click Undo next to the action. Letterslot moves the file back and removes the tags it added. If you moved the file elsewhere in the meantime, it tells you instead of guessing.
Does Letterslot delete files?
No. It never deletes files permanently. Actions like “after 7 days” move files to the Trash, where you can still restore them.
What happens after the 14 days?
Letterslot stays free with 2 rules and 1 watched folder, including journal, Undo and recognition on your Mac. Pro unlocks the rest for €24 once, for 2 Macs.
Can it do my taxes?
No. The receipts page collects invoices and receipts per month and exports them as a ZIP with PDFs and a CSV list. It is not tax advice and does not promise that your receipts are complete or meet a tax office's requirements. Please check the recognized values.
More answers in Support.