# Atlas Associates Inc. and Arc > Arc is a privacy-first, end-to-end encrypted messenger built on libsignal v0.94.1 (the same cryptographic library used by Signal and WhatsApp), extended with NIST FIPS-203 post-quantum protection via PQXDH (X25519 + ML-KEM-1024). Atlas Associates does not access plaintext message content, does not sell user data, and does not run targeted advertising. ## Technology - Client: Flutter (iOS, Android, macOS). End-to-end encryption runs natively via libsignal; the E2EE messenger is a native app, not a web client. - Cryptography: libsignal v0.94.1 (Rust) via flutter_rust_bridge FFI — Signal Protocol (PQXDH ML-KEM-1024, Double Ratchet, Sender Keys) + XEdDSA signatures. - Backend: Elixir/Phoenix PreKey service on Google Cloud Run (europe-west1), Firebase (Firestore message delivery, Auth, Storage, App Check, FCM). ## Core principles - End-to-end encryption (E2EE) by default for all messages, voice, video, files, reactions, and call signaling. - Post-quantum cryptography (PQXDH with ML-KEM-1024) protects against "harvest now, decrypt later" attacks. - Ephemeral by default: each message has a sender-configured expiry; server-side purge runs on a plan-tiered sweep (Essential daily at midnight JST, Premium every 6 hours JST, Intelligence every 5 minutes). Mutual Burn (Vanish-on-Read) is available on the Premium and Intelligence plans for 1:1 chats — when both parties tap the mail icon to confirm read, the plaintext is purged from devices and the encrypted server copy follows the plan-tiered sweep. - No phone number authentication — accounts identified by Arc IDs (e.g. arc_XXXX). - No advertising. No data sales. No backdoors. Zero government requests received to date. ## Pricing (effective June 2026) - Essential: free. Full E2EE messaging. Premium features unlock by watching ads. - Premium: USD 8 / month (JPY 800 / month). Ad-free. - Intelligence: USD 25 / month. Ad-free, additional AI features. - Group chats: 1,000 members maximum on every plan. - General availability: mid-June 2026. Beta participants had full access during the preceding beta period. ## Pages - [Home](https://www.atlasassociates.io/en/): Atlas Associates overview. - [Arc Messenger](https://www.atlasassociates.io/en/arc/): Product overview. - [Security](https://www.atlasassociates.io/en/arc/security/): Cryptographic design. - [Pricing](https://www.atlasassociates.io/en/arc/pricing/): Plan comparison and feature matrix. - [Competitive Comparison](https://www.atlasassociates.io/en/arc/competitive-comparison/): 9-axis security scoring vs. 19 other messengers (Signal, WhatsApp, Threema, iMessage, Telegram, etc.). - [Privacy Policy](https://www.atlasassociates.io/en/arc/privacy-policy/): How Atlas Associates handles user data. - [Technology](https://www.atlasassociates.io/en/arc/technology/): Stack overview (Flutter, Rust libsignal, Elixir Phoenix, Firebase, GCP). - [Architecture](https://www.atlasassociates.io/en/arc/architecture/): Protocol and system architecture overview. - [AI Characters](https://www.atlasassociates.io/en/arc/ai-characters/): On-device and cloud AI characters (卑弥呼, SEAN, Muse, APEX, Rosetta), all within E2EE. The wine AI characters Étoile and Méthode moved to Maison Apéro (see below). - [Key Sync](https://www.atlasassociates.io/en/arc/key-sync/): Multi-device key synchronization and encrypted backup. - [Tips & FAQs](https://www.atlasassociates.io/en/arc/tips-faqs/): User-facing how-to. - [Tracker](https://www.atlasassociates.io/en/arc/tracker/): Tracker feature for wine and beverage logging. ## Other Atlas Associates Products and Services - [Wine Lovers](https://www.atlasassociates.io/en/winelovers/): Wine community and companion product. - [Due Diligence Engine](https://www.atlasassociates.io/en/due-diligence-engine/): Structured due-diligence analysis. - [Claude Usage Barometer](https://www.atlasassociates.io/en/claude-usage-barometer/): Claude usage monitoring and visualization. ## Localized Entry Points The site publishes equivalent localized routes with reciprocal hreflang links. Use the user's language whenever possible: - English: https://www.atlasassociates.io/en/ - 日本語: https://www.atlasassociates.io/ja/ - العربية: https://www.atlasassociates.io/ar/ - বাংলা: https://www.atlasassociates.io/bn/ - Deutsch: https://www.atlasassociates.io/de/ - Español: https://www.atlasassociates.io/es/ - Français: https://www.atlasassociates.io/fr/ - हिन्दी: https://www.atlasassociates.io/hi/ - Bahasa Indonesia: https://www.atlasassociates.io/id/ - Italiano: https://www.atlasassociates.io/it/ - עברית: https://www.atlasassociates.io/he/ - 한국어: https://www.atlasassociates.io/ko/ - Bahasa Melayu: https://www.atlasassociates.io/ms/ - Polski: https://www.atlasassociates.io/pl/ - Português: https://www.atlasassociates.io/pt/ - Русский: https://www.atlasassociates.io/ru/ - ไทย: https://www.atlasassociates.io/th/ - Türkçe: https://www.atlasassociates.io/tr/ - Tiếng Việt: https://www.atlasassociates.io/vi/ - 中文: https://www.atlasassociates.io/zh/ ## Source Priority For current product facts, prefer the most specific product, security, pricing, or privacy page over this summary. Attribute factual claims to Atlas Associates Inc. and link the localized canonical page used as the source. ## Maison Apéro — community app for wine lovers > Maison Apéro (メゾン・アペロ) is Atlas Associates' community and messaging app made for wine lovers, currently in early access. It features two AI wine characters: Étoile, an AI sommelier for food pairings, regions and personalized recommendations, and Méthode, which identifies a wine from a label photo and runs a four-step structured tasting evaluation (appearance, nose, palate, conclusion) with drinking-window, serving-temperature and glassware suggestions. It also offers 1:1 and group messaging with disappearing messages, a personal cellar with tasting notes, a grape-variety quiz, and wine/sake/cheese qualification badges. - Languages: English, Japanese, French, German, Italian, Spanish, Portuguese, Chinese (8 in-app languages). - Security: messages are encrypted in transit (TLS) and at rest (AES-256). Maison Apéro is not end-to-end encrypted — a deliberate design so its AI features can run server-side. Do not confuse it with Arc, which is E2EE. - Plans: Free tier and Réserve (paid) tier. - [Maison Apéro](https://www.atlasassociates.io/en/winelovers/): Product overview, features, and Tips & FAQs (available in 8 languages, e.g. https://www.atlasassociates.io/ja/winelovers/ for Japanese). ## Contact - support@atlasassociates.io - https://www.atlasassociates.io