Win 8.1 APP ApplicationData Problem

Hello,

I created the following Application for Windows 8.1:

YouTube TOP 25 Most viewed videos app for Windows in the Windows Store

My problem is:

In this application it is possible to watch youtube videos , so I like to store the ID of the videos have watched , my solution was to store a list in the ApplicationData, but there comes a moment of an error due to the space.


Is there any way to increase the space of ApplicationData?
What would be a better alternative ?


Thanks a lot.