Bank-level encryption option
Enable ChaCha20‑Poly1305 E2E in Settings for café, hotel, or guest Wi‑Fi. Both sides negotiate the protected channel before the data phase.
Security
Bank-Level Secure WiFi File Transfer
FileFly defaults to direct local transfer for speed. Optional ChaCha20‑Poly1305 end‑to‑end encryption and PIN confirm deliver bank‑grade protection when the network is less trusted — without cloud servers.
Protection layers
Why FileFly feels bank‑grade
We do not claim a bank certification — we use the same class of authenticated encryption (ChaCha20‑Poly1305) trusted in modern secure messaging, plus human PIN gates and a local‑only path so files never sit in a FileFly cloud mailbox.
Local-first architecture
Transfers stay on your LAN. There is no FileFly cloud mailbox sitting between the two phones.
Optional ChaCha20‑Poly1305
Authenticated encryption when you want public‑Wi‑Fi peace of mind. Off by default at home for max throughput.
PIN confirmation
Sender displays a 4‑digit PIN. Receiver must enter it (with attempt limits) before the data phase begins.
Human gates
Incoming offers show size, encryption state, and storage readiness so you accept with eyes open.
Install only what you intend
APK install uses Android’s package installer and requires allowing installs from FileFly.
Practical guidance
On home Wi‑Fi, leave encryption off for maximum throughput if you trust the network. On cafés, hotels, or guest networks, turn encryption on and keep PIN confirm enabled for bank‑level security of the wireless stream.
FileFly still asks for the Android permissions needed to pick media, scan QR codes, run background transfers, and optionally install received packages — each with an in-app explanation. See permissions and WiFi file transfer FAQ.