Swiss Phone Book, developed by Swisscom Directories AG, is the official phone book app for Switzerland. This app is designed to help you find telephone numbers and addresses of private individuals, companies, and services in Switzerland and Liechtenstein. It also allows you to identify incoming calls, detect and block unwanted telemarketing calls, and view your call history.

The caller identification feature of this app is particularly useful as it lets you know who is calling you even if the number is not in your address book. The app can also automatically block known and verified spammers. Swiss Phone Book requires certain permissions to function optimally, such as internet connectivity, location, and phone calls. These permissions enable you to search around your location, add and merge entries to your address book's account of choice, and directly make phone calls from within the app.

Overall, Swiss Phone Book is a reliable and user-friendly app that provides accurate information and helps you avoid annoying telemarketing calls.