TODO.md

TODO — Email Client Feature Backlog

Feature list derived from FairEmail (open-source, privacy-oriented Android email client by M66B), based on its README, Play Store description, and FAQ. Features marked (pro) are paid "pro" convenience/advanced features in FairEmail; everything else is free there.

Contents

• Extensibility & Plug-ins
• Accounts & Protocols
• Message List / Inbox
• Reading Messages
• Composing
• Search
• Privacy & Security
• Encryption
• Notifications
• Organization, Rules & Automation
• Sync & Offline
• UI / UX
• Project / Meta

Extensibility & Plug-ins

The client should be highly optimizable via plug-in abilities: core stays minimal, and capabilities are added through well-defined extension points rather than baked in.

v1 spec: user-stories/typescript_plugin_system.md (plus MailProvider/MailIntelligence/MailStore interfaces for backend plug-ins). Items below stay unchecked until implemented.

• Plug-in architecture — a stable, versioned extension API with plug-ins discovered/registered at startup and loadable without modifying core code
• Mail-platform plug-ins — new email platforms ship as MailProvider proxy implementations registered into the ProviderRegistry (Gmail first; IMAP, Outlook, etc. as plug-ins)
• Message-view plug-ins — hooks into the read pipeline (e.g. translation, summarization/AI, tracking-pixel stripping, iCalendar rendering) as installable units
• Compose plug-ins — hooks into the compose pipeline (e.g. grammar/spell check, templates, Markdown, encryption) as installable units
• Action/rule plug-ins — custom triage actions and rule conditions/actions (webhooks, automation intents) contributed by plug-ins
• UI extension points — plug-ins can add message-list actions, toolbar buttons, and settings panels without core UI changes
• Capability negotiation — plug-ins declare what they support (mirroring capabilities()), so the UI shows only applicable affordances
• Plug-in isolation — a misbehaving plug-in degrades gracefully (disabled with an error surfaced) and cannot break core mail flows
• Plug-in management UI — enable/disable, configure, and view installed plug-ins from settings

Accounts & Protocols

• Unlimited accounts — no cap on number of configured email accounts
• Unlimited email addresses — unlimited identities/aliases per account, with default CC/BCC per identity and identity matching for replies
• IMAP support — full two-way IMAP synchronization
• POP3 support — basic POP3 accounts (with "leave messages on server" option)
• SMTP support — sending via standard SMTP
• IMAP IDLE push — real-time push messages without polling (plus IMAP NOTIFY where supported)
• Quick setup wizard — auto-detects server configuration for virtually all providers (Gmail, Outlook, Yahoo, iCloud, etc.)
• OAuth sign-in — OAuth for Gmail, Outlook/Office 365, Yahoo, Mail.ru, Yandex; custom OAuth via importable provider XML
• Auth methods — CRAM-MD5, LOGIN, PLAIN, NTLM, XOAUTH2; client certificates selectable per account/identity; SNI support
• SSL/TLS and STARTTLS — with option to allow invalid certificates/plain-text only when explicitly chosen
• Auto discovery — automatic server settings lookup for manual setup
• Copy accounts/identities — duplicate an existing account/identity configuration
• Works without Google services — no Firebase Cloud Messaging, runs on de-Googled devices
• (Explicit non-goals in FairEmail: no Exchange Web Services / ActiveSync / JMAP)

Message List / Inbox

• Unified inbox — combined inbox across accounts (optionally per account or per folder); folders can be added/removed from it
• Generic unified folders — unify any folder type across accounts
• Conversation threading — messages grouped into conversation threads
• Message previews — snippet preview lines in the list (also sendable to smartwatches)
• Swipe actions — configurable swipe left/right targets (archive, trash, snooze, etc.), per account too
• Batch operations — long-press + hold + swipe to select ranges; mark all read, move/delete all, etc.
• Browse messages on server — scroll past locally synced messages to fetch older ones on demand
• Saved searches — e.g. unified starred-messages view implemented as a saved search
• Sort/filter options — folder sorting, dimmed display for remotely deleted/moved messages
• Colored stars — star messages in multiple colors (pro); synchronizable via IMAP keywords
• Local notes — attach private notes to messages
• Keywords — show/set IMAP keywords (message tags) in the header
• Gmail specifics — Gmail label/category sync, raw Gmail search operators, label-aware copy

Reading Messages

• Safe message view — reformatted view with styling, scripting, and unsafe HTML removed
• Show original message — optional full original HTML view (embedded WebView), openable in browser
• Auto-expand rules — sensible auto-expanding of messages in a conversation
• Pinch to zoom — zoom message content and text size
• Image handling — embedded vs. external image distinction, tap image to see its source URL, auto-rotate/resize, GIF display
• Attachments — open/save attachments with confirmation; winmail.dat awareness
• Calendar invitations — view iCalendar invites; accept/decline (pro); add message to calendar (pro); auto-store invites
• Message headers — view full headers on demand
• Print messages — print/export a message
• Text-to-speech — read out sender/subject (non-Play builds)
• Translation — integrated DeepL translation support
• AI assistance — optional OpenAI (ChatGPT) / Gemini integration for summarizing etc.
• Contact photos — from address book, identicons, gravatars/favicons as contact photos
• Navigation — swipe to previous/next conversation, go-to-next on archive/delete, tablet two-column mode

Composing

• Rich text editing — common text styles (size, color, bold/italic, lists, etc.)
• Plain-text-only sending — per message or per identity
• Markdown support — compose with Markdown
• HTML signatures — per identity, including local images
• Reply templates — reusable answer templates, insertable or used to create drafts (pro)
• Quote selected text — replying with a selection quotes only that text
• Reply/forward options — reply-all/sender toggle, forward, send as attachment, resend (rfc2822), hard bounce (DSN)
• Send after selected time — scheduled/delayed sending (pro)
• Undo send — cancel from the outbox before it goes out
• Attachment reminder — warns when you mention attaching but didn't
• Contact groups — insert an Android contact group's addresses
• CC/BCC management — show/hide fields, default CC/BCC per identity
• Voice notes / audio recording — record and attach audio
• Auto vCard attachments — automatically generate vCard attachments (pro)
• Grammar/spell check — LanguageTool integration
• Read/delivery receipts — request and process delivery/read receipts (sets $Delivered/$Displayed keywords)
• Large-file sharing — "Send" (Firefox Send-style) integration for big attachments

Search

• On-device search — case-insensitive partial-text search across sender, recipients, subject, keywords, and body
• Server search — continue search on the IMAP server, per folder/account
• Search scopes — unified inbox searches all accounts; folder search scoped to folder
• Search filters — with/without attachments (and attachment type), folder search, search suggestions
• System-wide search — select text in any app and "Search email" for it
• Gmail raw search — raw: prefix for Gmail search operators
• Search indexing — optional whole-word index for much faster on-device search (pro)
• Settings search — search within the app's settings

Privacy & Security

• Reformat messages — strips active/deceptive content to prevent phishing
• Confirm showing images — images blocked until confirmed, to prevent tracking
• Tracking-image blocking — attempts to recognize and disable tracking pixels (Disconnect tracker-protection lists)
• Confirm opening links — link confirmation with full URL display; choose how links open; per-domain trust
• Remove tracking parameters — strips tracking parameters from links (optional Adguard rules)
• Authentication warnings — warns when messages fail DKIM/SPF/DMARC checks; "safely transported" indicator
• Spam blocklists — optional sender/server checks against DNS blocklists (Spamhaus, Spamcop, Barracuda)
• VirusTotal integration — optionally scan attachments via VirusTotal
• Biometric/PIN app lock — protect the app with fingerprint/PIN (pro)
• Password-protected content — encrypt message content with a password for any recipient
• Certificate transparency + DNSSEC/DANE — optional stricter connection verification
• No third-party data storage — mail data stays on device; no ads, no analytics/tracking (error reporting opt-in), no FCM
• No special permissions — minimal platform permissions
• Encrypted settings export — settings backup files are encrypted
• Sensitivity header — set/display message sensitivity (personal/private/confidential)

Encryption

• OpenPGP — sign/encrypt/decrypt via OpenKeychain, including Autocrypt support
• S/MIME — sign/encrypt/decrypt with certificates (pro)
• Semi-automatic encryption — encrypt by default when keys are available
• Hardware token support — e.g. YubiKey via OpenKeychain

Notifications

• Push notifications — near-instant new-mail notifications via IMAP IDLE, with a low-priority foreground-service notification to stay alive
• Grouped per-message notifications — individual notifications with actions (Android 7+)
• Configurable notification actions — choose which actions (archive, trash, reply, move, etc.) appear (pro)
• Per-account/folder/sender notification sounds & settings — via notification channels, Android 8+ (pro)
• Notifications for extra folders — get new-message notifications for any folder
• Notification light / badge count — LED support and unread-count launcher badges
• Smartwatch support — message previews on Wear/smartwatches; Android Auto support
• Quick-settings tile & app shortcuts — toggle sync, jump to compose, etc.

Organization, Rules & Automation

• Filter rules (pro) — per-folder rules with ordering, grouping, disable, and stop-processing
• Rule conditions — sender/recipient/subject/header/text contains, attachments (by type), absolute/relative time, regex, Jsoup HTML selectors, expression language (with functions like onBlocklist(), hasMx(), knownContact(), AI(prompt))
• Rule actions — mark read/unread, hide, suppress/silence notification, snooze, star, set importance, add keyword/notes, move (with $year$/$month$/$domain$ subfolder placeholders), copy/label, delete permanently, play sound, auto answer/forward with template, TTS, automation (Tasker intent), webhook
• Scheduled rule runs — run rules daily against messages older than N days
• Automatic message classification — on-device learning to auto-file messages into folders (pro)
• Snooze messages/conversations — hide until a chosen time (pro)
• Synchronization scheduling — sync only during defined schedules/periods (pro)
• Folder management — create/delete folders, per-folder sync/download/keep settings, sub-folders, change system folder mapping
• Auto-delete old messages — per-folder automatic cleanup (e.g. empty trash after N days)
• Cross-account moves/copies — move or copy messages between accounts
• Local contacts — auto-collected suggestion contacts, import (incl. Outlook), contact groups, favicon photos

Sync & Offline

• Two-way synchronization — full bidirectional sync of read/starred/moved/deleted state
• Offline storage and operations — read, compose, and queue actions offline; operations replay when connected
• Sync on demand — manual/periodic sync modes as alternatives to always-on push
• Keep starred messages — option to always keep/sync starred messages
• Fetch more/older messages — download and retain older mail per folder on demand
• Battery friendly — designed for low battery usage
• Low data usage — configurable download size on metered connections, roam-like-at-home option
• Cleanup — periodic cleanup of orphaned local files
• Export/import settings — full settings backup/restore (export is (pro)); optional OS-level backup
• Cloud sync — optional sync of app configuration across devices

UI / UX

• Material design — including dark and pure-black themes, Material You colors, multiple theme variants
• Deliberately minimalistic — no bells and whistles, focus on reading/writing
• Highly customizable message view — density, columns shown, action bar top/bottom, compact folder view
• Account/identity/folder colors and avatars (pro) — color-coding throughout the UI
• Tablet/landscape mode — two-column master/detail layout
• Navigation drawer — folder/account navigation, customizable entries
• Message list widget (pro) and unread-count widget — home-screen widgets, per-account selectable
• Small footprint — app under ~30 MB
• Localized — community-translated via Crowdin
• Runs on Android 5+ — phones and tablets (this project targets iOS/Android/web via Capacitor instead)

Project / Meta

• 100% open source — GPLv3, original work (not a fork)
• Privacy policy & no vendor lock-in — standard protocols only; bring your own email address
• Actively maintained — Play Store, GitHub (with in-app update check), and F-Droid releases