Uploading image to firebaseStorage

I installed 2 libraries (firebase itself and angularfire2)
I’m trying to upload image to firebase server using these codes

//this.src is image path generated from the ImagePicker plugin
// public b64: Base64 , declared as a constructer argument
this.b64.encodeFile(this.src).then((base64File: string) => {
        this.storeBack.uploadImg(base64File).then((storage)=>{
            // I cannot detect what is happening here - because I have to build the project to APK - so cordova plugins work without issues 
        });
      });

  uploadImg(src)
  {
    let storageRef = storage().ref('image.jpg');
    const img = 'data:image/jpeg;base64,' + src;
    return storageRef.putString(img , 'data_url');
  }

testing cases like this is killing the time - because I have to make edits/build/test (don’t have a debug solution on a real Android device) , so have to remake edits/build test … and so on