Once you create a favourite (See below). It , it will appear on your favourites tab. Click here for how to create a favourite.
Every time you re-open your app or open the favourite by clicking on it, it will check to make sure all your documents are the latest version.
All of this happens in the background so you don't need to do anything to get the latest version of your document list.
Alternatively you can also go to the settings tab, and click refresh - Synchronise to update your favourite list to get the later version of your documents.