Sarah Tew/CNET

There was a time not so long ago when MP3 players were a hot and essential technology, and Apple's best-selling product was the iPod. Now with smartphones and tablets, though, there are many other devices that make great music players. But even if the MP3 player's best days are waning, there are still a number of great products available. Here are our top picks.

iPod Touch

iPod Touch photo.
Sarah Tew/CNET

Apple's iPod Touch has been CNET's top-rated MP3 player for five years running. With a base model that starts at $229, it is not an inexpensive product, but the breadth of features it offers is unmatched in this category.

Apps, games, e-mail, maps, videos, books, and much, much more are all packed inside an incredibly thin, lightweight design. Best of all, music fans will appreciate that Apple includes its own music download store (iTunes) for browsing and purchasing songs over Wi-Fi, as well as support for nearly every major music service on the planet (Pandora, Spotify, Rhapsody, Amazon, and more).

SanDiskSansa Clip Zip

Josh Miller/CNET

The iPod Touch may offer the best range of features, but if you're looking for the best value, look no further than the Sansa Clip Zip.

With models priced as low as $40, this lightweight, clip-on MP3 player is the perfect accessory for the gym or any situation in which you'd rather not put your precious gadgets at risk.

Unlike many of its inexpensive competitors (such as the iPod Shuffle), the Sansa Clip Zip includes a color screen for navigation, and features such as FM radio, a voice recorder, a stopwatch, and microSD memory storage expansion.

Why buy a dead technology?
As I mentioned, the reason MP3 players aren't popular anymore is because most modern cell phones can adequately double as a portable music player.

If you're already paying for cell phone service, but don't yet have a phone that is capable of being used as an MP3 player, I'd strongly suggest a phone upgrade as your first course of action. In many cases, the carrier-subsidized cost of a new phone on contract can be less than the cost of even the least-expensive MP3 player.

The popularity of inexpensive tablets is another reason why people are skipping over MP3 players. Products such as the Amazon Kindle Fire or Google Nexus 7 can handle music playback in addition to games, e-mail, books, apps, and Web browsing. In terms of pure entertainment value, these tablets pack a bigger punch and can be bought for less than $200.

Finally, if your biggest concern is portability, consider investing in a pair of wireless Bluetooth headphones to use with your cell phone. Every modern cell phone supports Bluetooth audio. With it, you can keep your phone safe and secure in your pocket or gym bag and have it send wireless audio to your Bluetooth-compatible headphones. Likewise, playback and volume controls on your headphones can send information back to your cell phone.

Before you buy
With all of that said, if you still really want to buy an MP3 player, here's what you should know.

1. If you can save money by buying last year's model, go for it. The innovation in MP3 players has been flat for years, and a 2011 MP3 player is going to work just as well as one released today.

2. Know what format your music collection is in. If you've been purchasing your music from iTunes, you may be surprised to learn that you've been downloading AAC files (Apple's preferred format) instead of MP3 files. Fortunately, there are a lot of AAC-compatible music players out there that will work with Apple's unprotected AAC format.

The same is true of audiobooks. There are many proprietary audiobook formats out there, such as Audible and Overdrive. Check to see if your prospective MP3 player is compatible with these formats. If you get audiobooks on loan from your local library, ask your librarian for a list of compatible devices.

3. Don't skimp on headphones. Whether you're buying an MP3 player as a workout companion or a safe home for your music collection, the headphones you connect to it can make all the difference.

It is not unheard of to spend more on your headphones than on your MP3 player. It can make a huge difference in sound quality. For athletes, a pair of fitness-oriented headphones will help minimize discomfort.

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