SkyPhone is a free and easy-to-use calling app that offers clear and high-quality voice and video calls to its users. Developed by QuadSystem and available for Android devices, the app has been downloaded over 5 million times. One of the best features of SkyPhone is that it doesn't require any personal information to use, and you can start using it right away.

The app has a simple user interface with no ads, making it easy to navigate. With the Allow Contacts Only feature, you can block calls from unregistered contacts, and the app allows you to connect only with those you want to. This makes it an ideal app to make calls to your loved ones. Additionally, the Noise Cancel Feature ensures that you can hear the other person clearly, even if you're in a noisy environment. You can also enjoy talking for a long time with the Call Sound Quality setting set to Low, even if you are in an area with a weak signal or your data speed is reduced.

Overall, SkyPhone is a great app for those looking for a simple and free calling app that offers high-quality voice and video calls. Its user-friendly interface, no-registration feature, and noise-canceling function make it an excellent choice for those who want to stay connected with their loved ones.