Privacy policy

Half a Knife reader app · last updated 22 September 2026

This is a book, sold by one person. There is no advertising in this app, no analytics, no tracking, and nothing is sold to anybody. The short version: we keep your phone number so you can sign in, and a record that you paid. That is close to all of it.

What is collected

WhatWhy
Your phone number It is your account. It is how you sign in, and how a payment is matched to you.
A device identifier An identifier made from your phone’s own Android ID and scrambled so it cannot be traced back, plus your phone’s make and model so you can recognise it in a list. It stays the same if you reinstall the app, so a reinstall does not use up a phone. This is how a copy is limited to two phones. It is not an advertising identifier and it is not shared with anyone.
Purchase records The Telebirr transaction number you enter, and Telebirr’s own confirmation of the payment as it reaches our account: the payer’s name as Telebirr shows it, the last four digits of their number, the amount and the transaction number. That is how a payment is matched to your order and your book unlocked.
Your IP address Used briefly to stop automated abuse — mainly to stop scripts hammering the service. It is held in short-lived counters, not in a log of who read what.

What is not collected

Who else sees it

Two parties, each for one narrow job:

Nothing is sold, rented, or handed to advertisers. Nothing is disclosed to anyone else unless we are legally compelled to, and no such request has ever been received.

A note, given what this book is about. This app is sold to readers in Ethiopia, and the book is a political memoir. We deliberately do not keep a record of what any reader reads or when — not as a courtesy, but because a record that does not exist cannot be demanded of us.

How long it is kept

Your account is kept until you delete it. Sign-in sessions expire after 90 days. One-time codes are deleted within a day of being used or expiring. After you delete your account, the record that a payment was received is kept as an accounting record, with your phone number removed from it.

Deleting your account

Two ways, both of which erase the same things:

Deleting removes your phone number, your devices and your access to the book. It does not refund the purchase.

Children

This app is not directed at children. The book describes political violence and is intended for adult readers.

Security

Everything travels over HTTPS. The book itself is encrypted and is decrypted only inside the app, on your phone, using a key held in your phone’s hardware keystore.

Changes

If this policy changes in a way that affects what is collected, the date at the top changes and the app will say so at sign-in.

Contact

Baye Teshager Asmamaw · Winchester, Virginia, United States
[email protected]

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