How to access files under assets folder of other apk's?

This will list all the files in the assets folder:

AssetManager assetManager = getAssets();
String[] files = assetManager.list("");

This to open a certian file:

InputStream input = assetManager.open(assetName);

If you want to access file from assets folder use the following code:

InputStream is = getAssets().open("contacts.csv");
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(is);
HttpContext localContext = new BasicHttpContext();
HttpResponse response =httpClient.execute(httpGet, localContext);
BufferedReader reader = new BufferedReader(new 
InputStreamReader(response.getEntity().getContent()));

For example: If you have the .ttf file in your assets folder: then you used like this:

Typeface font = Typeface.createFromAsset(getAssets(), "MARKER.TTF");

Here is link: http://developer.android.com/guide/topics/resources/accessing-resources.html#ResourcesFromCode