Privacy & Data

ScamShield Nepal is built around one rule: your messages stay on your phone.

What never leaves your phone

• The full text of your SMS messages
• Your actual phone number, or the actual phone number of a sender
• Any messages you've marked as "Not a scam" or deleted

What may be sent — and only when needed

For messages your on-device AI isn't confident about (the "medium confidence" range — see How It Works), ScamShield sends a small metadata package to the cloud for a second opinion:

Sent	Example	Not the same as
A one-way hash of the sender's number	a1b2c3d4… (64 characters)	The actual phone number — cannot be reversed
Links found in the message	https://example.com	The surrounding message text
Message length	142	The message content
Whether the message uses Nepali script	true / false	The message content
On-device confidence score	0.71	—

The server never stores message text — only the hashed sender, the final label, and a timestamp.

Phone number hashing

Sender numbers are converted using SHA-256, a one-way cryptographic hash. This means:

• The same number always produces the same hash, so repeat-offender numbers can be recognised
• The original number cannot be recovered from the hash

Correcting a result ("Not a scam")

If you mark a message as "Not a scam" in your Scam Inbox, ScamShield sends only:

• The message ID (a random local identifier)
• The hashed sender
• The corrected label (Safe) and the original label (e.g. Scam)

The message text is never included.

How long is data kept?

• On your device: flagged messages are automatically deleted after 90 days
• On the server: only hashed sender, label, and timestamp — no message content is ever stored

Full-text cloud analysis (opt-in only)

A future premium feature may offer full-text cloud analysis for even better accuracy. This will always be off by default and require your explicit opt-in.