Modify existing Android application - simple changes

General information for the app: App is a media player. Media is streamed to player on request.
Kind of development: Customization of existing app
Description of requirements/features: 3 Modifications are required:

1) currently the media available is hard coded within the app as an ArrayList (for proof of concept purposes) This now needs to be read from a text file that is delivered to the device. The text file contains the entire string which is used to create the ArrayList.

2) a link is required within the settings window of the current app to access another app on the device called Watchdog - this app delivers the text files for point 1

3) a link to config the WiFi needs to also be added to the settings window.
Specific technologies required: JAVA
Extra notes: The Watchdog app and the server based php files for creating the text files delivered by the Watchdog already exist and function correctly, the only requirement here is for the modifications to the App mentioned in this requirement.

The attached file shows the hard coded string data for createDummyRadioList, createDummyAudioBookList and createDummyPodCastList
Each of these "lists" will need to come from separate text files that will be known as radio.txt, audiobk.txt, podcast.txt each file lives within the /storage/sdcard/Download folder on the android tablet.