Dial Defender 2.5 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. The actual developer of this software for Mac is MAKI Enterprises, Inc. Dial Defender for Mac belongs to Security Tools.
From the developer:
Dial Defender is a security program that can automatically kill connections to your Mac from specific phone numbers calling it. Features include: Monitor your registered phone number. When Internet settings is rewritten, it intercepts and warns. (Passive defense) Prevent the settings rewriting. (Active defense) Multiple phone numbers, Multi user are supported. Easy operation. Check your numbers and click setting button.
You may want to check out more software for Mac, such as Dial!Fritz, Moon Dialer or MC Dialer, which might be similar to Dial Defender.
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Antivirus