Option to modify default theme components and use a custom font globally. Great documentation with examples

Easy to use components, it has wide variety of responsive components that can be easily plugged into your react native code to develop beautiful UI for your mobile app. There are very less libraries for UI components for react native, native base provides those components. Can be used with gatsby, next js and expo clients. Integration is seamless and with multiple options for different platform integrations hence giving much freedom on the underlying structure

NativeBase is a UI framework for ReactNative.It enables developers to build professional UI Screens. Its work with Android as well as IOS. The important thing is they are upgrading continuously along with ReactNative so the developers can easily migrate their code in NativeBase.They have an example UI framework App in AppStore and Expo for Beginners.