Email newsletter reader.

Collect, organize, and enjoy email newsletters in a dedicated home that's not your personal inbox. No more email triage.

Your new newsletter workspace.

Letterboxx is a dedicated home for newsletters on Mac with smart filters, better reading tools, and Auto-Delivery to sort and route new issues automatically.

Reader Tools

Capture what matters inside every issue.

Highlight passages, navigate highlights, adjust zoom, print cleanly, and take action on unsubscribe links directly from the reader.

Five highlight colors with remove-single and remove-all controls
Built-in unsubscribe link detection and confirmation flow
Zoom in, zoom out, actual size, and print from native menu commands

Triage Flow

Turn newsletters into a calm reading queue.

Mark read/unread, favorite, move to trash, restore, and set reminders so long-form newsletters return exactly when you want them.

One-hour, evening, tomorrow, next-week, or custom reminder options
Reminder notifications with quick reschedule or clear actions
Safe trash workflow with restore and explicit empty trash command

Auto-Delivery

Route every newsletter automatically.

Set active rules that file new arrivals directly into the right Letterboxx.

Match on sender, recipients, subject, content, and more
Use all/any condition logic and ordered rule priority
Run rules on selected messages or your whole inbox on demand

Smart Filters

Find and seek.

Browse by Inbox, Unread, Today, Yesterday, This Week, Last Week, All, Favorites, Highlighted, Reminders, Trash, or custom Letterboxxes.

Instant sidebar search for sender and subject
Dedicated newsletter-focused navigation, not generic mail clutter

Accounts + Sync

Connect the way your mailbox works.

Use Gmail OAuth or standard IMAP credentials with provider presets and connection tests before saving.

Provider presets: Gmail, iCloud, Outlook, DreamHost, Custom IMAP
Per-account setup, test connection, and initial sync status

Native Mac

Keyboard-first and command-driven.

Use fast commands for new downloads, Auto-Delivery runs, highlighting, print, zoom, and app-wide windows like Activity Log and Statistics.

Purpose-built menu commands and shortcuts throughout
Works like a Mac app because it IS a Mac app, not a web shell in disguise

Personalization

Shape the experience to your reading style.

Choose visual and sound themes, list density and typography controls, sender badge behavior, and dock badge count source.

Customizable sounds for arrival, routing, favorite, trash, restore, read/unread

Letterboxxes

Letterboxxes are your custom newsletter folders inside Letterboxx. Create focused spaces for each topic, then file newsletters manually or route them automatically with Auto-Delivery.

Focused Organization

Give every newsletter a purpose-built home.

Separate your reading stream into intentional Letterboxxes so your inbox stays clean and your best newsletters stay easy to find.

Create Letterboxxes for topics, projects, or interests
Move newsletters directly into a Letterboxx using the contextual menu or drag and drop
Use Auto-Delivery rules to route new messages into the right Letterboxx automatically

Context menu in Letterboxx message list showing move options for Letterboxxes

Quick Access + Simple Setup

Create and manage Letterboxxes in seconds.

Letterboxxes live directly in the sidebar and can be created on demand, so setup and organization stay one click away.

Open sidebar actions to create and manage your Letterboxxes instantly
Name and configure a new Letterboxx in a focused modal flow
Keep your Letterboxx system aligned with how you actually read using sort or drag and drop

Appearance

Tune Letterboxx to your reading style with theme controls, typography settings, and calmer visual defaults.

Visual Theme

Choose the look that matches how you read.

Switch themes instantly and keep your reading experience aligned with your environment and focus level.

Theme modes include System, Light, Dark, Newspaper, E-Ink, and Tiger
Quickly preview and switch without leaving your reading flow

Letterboxx appearance settings window with theme and layout options

Newsletter List

Tune sizing, density, and visible detail.

Adjust the newsletter list so it surfaces exactly the information you want at a glance.

Choose the list font and row density
Set subject size, secondary text size, and sender badge size independently
Toggle sender name, date and time, status indicators, and unread indicator visibility

Highlighting

Mark important passages in any newsletter, keep them persistent, and return to them instantly through the dedicated Highlighted filter.

Mark what's important

Highlight your newsletter content

Use the toolbar or context menu to highlight text while you read.

Letterboxx stores every highlight per newsletter and keeps it attached to that newsletter
Use the Scroll to Highlight button to easily scroll through all of your highlighted content
Navigate, recolor, or remove highlights when revisiting

Letterboxx highlight workflow animation showing text selection and highlight actions

Persistent Recall

Every highlight becomes searchable context for later.

Any highlighted newsletters are automatically saved in the sidebar's Highlighted section so that your key marked content is never lost in the feed.

Highlights persist per message across app sessions
Highlighted filter shows only newsletters with saved highlights
Navigate, recolor, or remove highlights when revisiting

Letterboxx sidebar and reader with highlighted content visible