You can munch the screen of a Blackberry leap i.e take screenshot, without having to download any screen muncher app for Blackberry 10 from the Blackberry app store.
You can simply get this done by making use of the side buttons on the Blackberry Leap smartphone.
Whenever you are ready to screenshot on Blackberry leap, press both the Volume Up and Volume Down keys (on the right side of the device) at the same time.
You’ll hear a click sound and your screenshot will be saved to your Camera folder on your Blackberry leap.
I hope this helps.
Kindly note that you can use same trick to take screenshot on Blackberry z10, q10, z3 etc.
NB: The button in between the volume keys of the Blackberry Leap is a dedicated physical button for BlackBerry Assistant; BlackBerry’s version of Siri, Cortana or Google Now.