ionic 2 - File storage path

Question

I need to download the pdf/word/excel file from external server in to my ionic application. Sample code below

 const fileTransfer: FileTransferObject = this.transfer.create();
    const url = 'https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf';
    fileTransfer.download(url, this.file.dataDirectory + 'file.pdf').then((entry) => {
    console.log('download complete: ' + entry.toURL());
  }, (error) => {
    console.log("error : " +error);
  });

I need to store all the files in my application itself not an external storage or an internal storage. Would this be possible?

By the way if we keep on store the files in the application itself then there is any application performance issue came?

Thanks AK