Android app showing text/pictures at a given time

I need an android application with 2 windows. The first window shows a list of tasks of which the user can select a task. Once the task is selected, a second window is opened. The second window shows the title of the task at the top left/middle, a count-down timer at the top right, a Pause button at the bottom and a window showing the current subtask (and the previous and next but these are greyed-out). When the user presses the back button during a task, the user is asked if he wants to save the progress or not. After this selection window 1 is shown Input (auto-loaded at startup): 1) Configuration XML-file: links to the used graphics, used text in all screens. 2) Data XML-file : Several elements of the type "task". Rough shape: <Task> <Name>Title<\Name> <SubTask> <Time>00:05</Time> <Action>Now you can go outside and?</Action> <\SubTask> <SubTask> ?.. <\SubTask> ? (all subtasks) </Task> The meaning of the parameter time is the duration of this task in minutes and seconds. After the 5 seconds in this example, the next SubTask is shown. Pressing the pause button stops the countdown. Pressing the pause button again results in resuming the countdown.