How can I add a Bitmap taken from the web (in the app i mean!) to the drawable resources? So i can access the Bitmap using R.drawable.bitmapN
The resources are compiled at the apk building time, so you cannot change it in runtime. If you want to have some identifier you can consider creating a shared preference where you can put in relation the downloaded image file with some id. But it will take some effort from you to implement the functionality.