Capabilities

Built for people who manage email at scale

People-centric delegation, local-first security, and AI tools that show their work.

People-centric views

Organize email by Person, not just account. Navigate relationships and see an aggregated timeline of interactions across all your connected inboxes. Each Person groups related Accounts so you never lose context.

  • Aggregated unread counts per Person
  • Identity-safe reply selection
  • Contact history across accounts

Operational limits

  • Requires consistent account-to-person mapping rules.
  • Cross-person merges are logged and reversible.

Multi-inbox delegation

Provide permissioned access to an Account or Person without sharing passwords. Assign role-based access tiers and maintain a complete audit trail of delegated actions.

  • Owner, Full, Triage, and Read permission tiers
  • Destructive action gating
  • Delegation audit logs

Operational limits

  • Role downgrades may hide previously available actions.
  • Owner role required for delegation policy changes.

Archive ingest

Import and search exported archives (MBOX up to 50 GB+, PST/OST up to 30 GB+, EML files) directly on your device. Deterministic progress tracking with checkpoint recovery for large imports.

  • MBOX, PST, OST, and EML format support
  • Checkpoint resume on interruption
  • Local FTS5 search indexing

Operational limits

  • Large PST imports may require extended indexing time.
  • Archive corruption is logged and surfaced per file.

AI tools

Summarize threads, extract entities, draft replies, and search your vaults using natural language. Every AI action shows its inputs and outputs in a glass-box pattern. Local AI runs by default; cloud AI requires explicit consent per action.

  • Local AI: priority scoring, categorization, entity extraction
  • Cloud AI: summarization, draft assistance, Q&A
  • Per-action consent sheet with payload preview

Operational limits

  • Cloud processing is disabled unless explicitly approved per action.
  • Provider outputs require human review before send.

Vault encryption

Every local data boundary is an encrypted Vault. Message content, search indices, and connection metadata are encrypted using XChaCha20-Poly1305 with per-Vault key hierarchies derived via Argon2id and HKDF.

  • Ed25519 event signatures
  • X25519 envelope encryption
  • Epoch-based key rotation

Operational limits

  • Vault unlock requires local key material and operator authentication.
  • Lost keys cannot be recovered by Twindevs.

Handoff plans

Generate guided action plans to transfer responsibility. Each Handoff includes full context, next steps, and a complete audit trail so nothing falls through the cracks when passing work between people.

  • Auto-drafted context bundles
  • Actionable checklists
  • Visible provenance and history

Operational limits

  • Handoff plans reference available thread metadata at generation time.
  • Final assignment is controlled by active role permissions.

Provider support

Connect to standard email providers and synchronize live messages seamlessly. All provider credentials are stored in your encrypted local Vault, never on our servers. OAuth-based connections where available.

  • Gmail and Google Workspace
  • Outlook and Microsoft 365
  • iCloud, Yahoo, Proton (via Bridge), generic IMAP/SMTP

Operational limits

  • Provider API limits can delay sync during peak traffic.
  • Bridge-based providers require local bridge availability.

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