apps that make the App Store's success

"App" has been a computing term for a lot longer than five years. But, on July 10, 2008, it began its journey to becoming a household word.

That's when Apple, a year after launching the iPhone, introduced its App Store to the world.

The online marketplace launched with 500 apps, mostly for established Web companies such as Facebook, eBay and Yelp. Today, it has more than 850,000. And, a couple of months ago, it passed a mind-boggling threshold, marking the 50 billionth app to be downloaded.

Apple can no longer claim proprietary ownership of apps, those mini-programs that continue to push the boundaries of what a mobile phone can do. Google launched its own app store, now called Play, less than a year after Apple. Today, it's on a path toward surpassing Apple's number of downloads. 2012: 'Angry Birds' soar into space Map apps: Google vs. Apple Instagram now lets you share video.

But the iPhone was the first smartphone most folks ever saw, and the App Store was the accessory that gave it extra usefulness. On this anniversary, we look at five iconic apps that got a huge lift from the App Store and expanded the capabilities of our phones.