iCall OS 18 is a free Android app designed to enhance the phone dialing experience with an OS 18 style theme. This all-in-one application combines a contacts list, recent calls history, and a favorite contacts list, alongside a T9 search keypad for easy access to contacts. Users can enjoy a full-screen caller ID and personalize their phone dialer with various customization options such as changing call screen backgrounds and setting wallpapers.

The app offers a range of features including call blocking for unwanted calls, dual-SIM support for managing multiple SIM settings, and the ability to schedule fake calls. Additionally, iCall OS 18 includes a slide-to-answer button for incoming calls, conference call functionalities, and a dark mode for battery optimization. Overall, iCall OS 18 presents a comprehensive and customizable phone dialer solution for Android users.