import RNFS from 'react-native-fs'
import RNApkInstallerN from 'react-native-apk-installer-n';
 
const filePath = RNFS.DocumentDirectoryPath + '/com.domain.example.apk';
const download = RNFS.downloadFile({
    fromUrl: 'apk file download url',
    toFile: filePath,
    progress: res => {
        console.log((res.bytesWritten / res.contentLength).toFixed(2));
    },
    progressDivider: 1
});
 
download.promise.then(result => {
    if(result.statusCode == 200){
        RNApkInstallerN.install(filePath)
    }
});