Arc vs iMessage
Apple-only — Arc is the cross-platform, phone-free equal.
iMessage is genuinely strong: it deployed the post-quantum PQ3 protocol in 2024 and is formally verified. But it is locked to Apple devices and tied to your Apple ID. Arc matches its post-quantum, audited cryptography while working on every platform, without a phone number.
Updated 2026-06-02 · evaluated by Claude Code Opus 4.8 Ultracode
Head-to-head score
Scores from the same independent 9-axis, 100-point rubric used across all 20 messengers. Higher is better.
Arc
89 / 100
iMessage
76 / 100
| Axis | Arc | iMessage |
|---|---|---|
| Crypto | 18 | 17 |
| Fwd/Bwd Secrecy | 14 | 13 |
| Post-Quantum | 14 | 14 |
| E2EE Coverage | 12 | 13 |
| Sender Privacy | 3 | 5 |
| Registration Privacy | 9 | 4 |
| Ephemeral | 11 | 1 |
| Verification UX | 4 | 4 |
| Multi-Device | 4 | 5 |
Why choose Arc over iMessage
01
Cross-platform and phone-free: Arc runs on iOS, Android, web and desktop with an Arc ID. iMessage is Apple-only and tied to your Apple ID (email or phone).
02
Dual-layer ephemerality: IGF + Mutual Burn give Arc a perfect 11/11 on the Ephemeral axis; iMessage scores 1 — edit/unsend is not timed deletion across servers.
03
BLE Mesh offline messaging and E2EE that stays free for everyone — outside Apple's walled garden.
What iMessage does well
- iMessage shipped full post-quantum encryption (PQ3) before almost anyone and is formally verified, with Contact Key Verification — deeply polished within the Apple ecosystem.
- As of iOS 26.5 it adds E2EE RCS to Android, though that path is MLS-based and not post-quantum.
The bottom line
If everyone you talk to lives entirely on Apple, iMessage is excellent. Arc (89 vs 76) brings the same post-quantum, audited cryptography to everyone — cross-platform, phone-free, and with dual-layer disappearing messages Apple does not offer.
Get Arc — E2EE, free for everyone
See the full 20-messenger comparison
How Arc's encryption works