Identify and block unwanted calls and SMS messages from unknown numbers. This app uses a vast database to provide caller information and protect you from telemarketers and scammers. Upgrade for unlimited requests and an ad-free experience.
Reviews of Number Book are mostly negative: the Utilities app is rated 3.8/5 from 466 App Store ratings. What users like most: useful app, fast and efficient. Top complaints: crashes and bugs, slow performance. Summarized from real user reviews.
1.7.5
January 22, 2026
Bug fixes and performance improvements
1 month subscription unlocks premium features
3 issues
App crashes on iOS 26
Login and registration issues
3 requests
Update for iOS 16 compatibility
Improve user interface and experience
Number Book acts as a leading unknown caller ID and spam blocker. It helps you identify and block spam calls or SMS messages and allows you to search for unknown numbers. The app is powered by a large database of phone numbers to provide accurate caller information.
You can enable spam identification and blocking through your phone's settings. The app then protects you from telemarketers, scammers, robocalls, and other fraudulent callers by identifying and blocking their calls and SMS messages.
The app is free to download and use, offering basic caller identification and spam blocking features. For an enhanced experience, there is a premium subscription available which removes ads, provides unlimited requests, and offers auto-renewal options.
The premium subscription offers unlimited requests and removes all ads. Pricing varies by country but includes monthly, 3-month, 6-month, and yearly options, with the cheapest being $1.99 monthly and $9.99 yearly.
The app allows you to search over one billion phone numbers worldwide, providing global coverage. This feature helps you identify the name of the caller for most numbers.
