With this article I am just trying to highlight a built in feature of BlackBerry 10 OS which is very useful for quick application navigation. Normally in gNewsReader application you would follow following screen flows
Subscriptions page -> feed articles list page -> feed article view page (detail page) and to get back you would go
feed article view -> feed article list -> subscriptions by clicking on back button in bottom toolbar.
Instead of this you can also swipe on bottom toolbar from left to right to get to subscriptions page directly from feed article view page