The iPhone 5 and the rumored iPad Mini might grab all the headlines, but one of Apple's bread-and-butter products, the iPod, continues to make headway. Though the old-school device typically gets little fanfare, this week Apple revealed a new TV spot (see it below) showcasing Technicolor versions of its new iPod Touch, Nano, and Shuffle bouncing around like small, rectangular break-dancers. But why, exactly, does Apple continue to make mp3 players when many of its other devices can do the same and then some? Here, four key reasons:

1. iPods are still a multi-billion-dollar business
"Nowadays, it's hard to find a single analyst that'll even mention the music players in their advice to shareholders," says Don Reisinger at CNN Money, and the pocketable little players represent just 3 percent of Apple's overall business. And iPod sales are down a "whopping" 20 percent for the April-June 2012 period compared to the same period in 2011. That said: iPods still generated $1.06 billion for the company during those three months this year.

2. They're a portal to Apple's digital market place
Consider the iPod touch the iPhone-lite, says Jason D. O'Grady at ZDnet. For Apple newbies, it functions as an entry point to all the apps, games, and music available in the iTunes App Store. While iPhone 5 owners clearly don't need one, the Touch is a "powerful iOS device that gets [kids, teens, and students] into the Apple ecosystem."

3. The iPod dominates the mp3 player market
During its last earnings call, Apple pointed out that iPod sales constitute more than 70 percent of the mp3 player market in the U.S., says Seth Fiergerman at Mashable. "Some might roll their eyes" that Apple is patting itself on the back for leading a market "it itself is cannibalizing," but the iPod is still "one of the leading ways that people consume music," especially with fewer competitors — such as Microsoft's discontinued Zune — in the space than ever before.

4. The iPod is a gateway product to other Apple devices
For me, "it all started with an iPod touch, a gift from my parents two years ago," says David Pierce at The Verge. "I've since bought a half-dozen more iPods, two iPhones, an iPad, and a MacBook Air. Somehow I'm sure Apple planned it that way. The touch is... the easy and kid-friendly device that has gotten so many people hooked on iOS."