API Version

The code is here. Just a little different from your example

private void initializeDropbox() {
AppKeyPair appKeys = new AppKeyPair(DROPBOX_APP_KEY, DROPBOX_APP_SECRET);
AndroidAuthSession session = new AndroidAuthSession(appKeys, DROPBOX_ACCESS_TYPE);
mDBApi = new DropboxAPI<AndroidAuthSession>(session);
//Create DropboxUtil class that will be used in this app's Javascript
DropboxUtils dropboxUtils = new DropboxUtils(this, appView);
appView.addJavascriptInterface(dropboxUtils, "DropboxUtils");

I understand about the new key pairs. Yes we have a separate key pair for each app. Just to check the code, I added the old key to the new code. I am assume that there isn't other parameter that would change between key pairs. If the code works with one set of keys, shouldn't it work with the other set. I didn't know if new app required a different api level from the time we create the other app. Nothing has changed in the code, but the keys.