apply from: "../../node_modules/react-native-vector-icons/fonts.gradle"
where you should replace node modules with your library path if its different
in ios you should manually install each of the fonts by downloading them and adding them into info.plist file. example :
<key>UIAppFonts</key> <array> <string>FontAwesome.ttf</string> <string>MaterialIcons.ttf</string> <string>MaterialCommunityIcons.ttf</string> <string>Montserrat-Black.ttf</string> <string>Montserrat-BlackItalic.ttf</string> <string>Montserrat-Bold.ttf</string> <string>Montserrat-BoldItalic.ttf</string> <string>Montserrat-ExtraBold.ttf</string> <string>Montserrat-ExtraBoldItalic.ttf</string> <string>Montserrat-ExtraLight.ttf</string> <string>Montserrat-ExtraLightItalic.ttf</string> <string>Montserrat-Italic.ttf</string> <string>Montserrat-Light.ttf</string> <string>Montserrat-LightItalic.ttf</string> <string>Montserrat-Medium.ttf</string> <string>Montserrat-MediumItalic.ttf</string> <string>Montserrat-Regular.ttf</string> <string>Montserrat-SemiBold.ttf</string> <string>Montserrat-SemiBoldItalic.ttf</string> <string>Montserrat-Thin.ttf</string> <string>Montserrat-ThinItalic.ttf</string> </array>