Apps (short for Applications) are actually not that new. Whenever I need some technology explained "in Plain English" - I turn to the Common Craft page. Somehow, Lee Lefever makes complicated topics easier to understand.
From the Common Craft page:
"We hear so much about apps today that it’s easy to think about them
being a fundamentally new phenomenon, but the truth is that we used apps
or “software applications” long before mobile phones. This video
explains what caused apps to evolve and what
new systems are in place that are making them so popular and useful
today."
Click here:
VIDEO: Apps Explained by Common Craft
I encourage you to check out other videos on the Common
Craft page as well!