apk downloaden und installieren

1Bitmap bmImg = null;
2URL myFileUrl =null;
3 try {
4 myFileUrl= new URL(fileUrl);
5 } catch (MalformedURLException e) {
6 // TODO Auto-generated catch block
7 e.printStackTrace();
8 }
9 try {
10 HttpURLConnection conn= (HttpURLConnection)myFileUrl.openConnection();
11 conn.setDoInput(true);
12 conn.connect();
13 int length = conn.getContentLength();
14 InputStream is = conn.getInputStream();
15
16 bmImg = BitmapFactory.decodeStream(is); //hier müsste dann der inputstream in eine apk decodiert werden. aber wiee??
17 } catch (IOException e) {
18 // TODO Auto-generated catch block
19 e.printStackTrace();
20 }