SecretBook 4.0 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This app's bundle is identified as com.i-graph.SecretBookAppAndImporter.
The actual developer of this free Mac application is Bookshelf Apps. The software lies within Security Tools, more precisely Personal Security. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The following version: 4.0 is the most frequently downloaded one by the program users. The app's installation file is generally known as SecretBook.zip.
From the developer:
SecretBook is an encrypted personal information database for Mac OS X. It allows you to easily and securely store all kinds of personal information…Data values are encrypted individually and are never decrypted unless needed. Even when you copy a value it is not decrypted until the corresponding paste operation.
You may want to check out more Mac applications, such as Key Holder or PasswordVault Lite, which might be similar to SecretBook.