Encrypted files, client state and participating services need a tested recovery plan that preserves the promised privacy boundary.
Integrity checks do not establish that a file belongs to the current account, version or action. Context and replay need explicit rules.
Key wrapping, RSA-KEM and historical HVKM describe different operations. A technical review must keep their evidence separate.
App signing, release authority and update freshness belong in the threat model of a private messenger.
A privacy review must follow diagnostics, crash reports and support exports as well as the encrypted database.
Private delivery and safe file processing are different controls. A practical review follows the attachment beyond decryption.
UseCrypt Messenger documentation separates call signalling, credentials and the stored conversation archive. Each boundary needs its own test.
Android Keystore and UseCrypt documentation show why preventing key extraction and controlling decryption operations require different evidence.
UseCrypt documentation and SQLite storage behaviour explain why a database review must follow journals, attachments and application states.
UseCrypt history and current privacy disclosure guidance help separate funding incentives, billing data and evidence about who can read a message.