Explore the best secure messaging apps for Android and iOS in 2025, as featured by Atharva System. Discover why Signal leads the pack—offering powerful end-to-end encryption, minimal metadata storage, disappearing messages, no ads or tracking. Learn about other top choices like Threema, which secures privacy with anonymous sign-up via app-store purchase, and Session or Olvid, offering decentralized networks and minimal to no personal data collection. Get insights for journalists, activists, privacy-minded users, and anyone wanting strong protection for their digital conversations.