Cannot exit app on my iPhone 5s

Getting into the app through Newsstand is a breeze. Navigating between and within issues takes a little getting used to. Once learned I am enjoying the experience.
The downgrade is due to the inability to exit from the app. When I close the app, it takes me to the Newsstand, where I am forced to stay (I cant get back to the phone features). The only way I found to get out of it is by cycling the power.

LongTermNatreader about National Geographic