Google, through the Google Play store, and Amazon.com are two of Apple's fiercest rivals when it comes to selling digital content, and for good reason: They have good products, and sometimes they have them at lower prices.
The same goes for Android users: They too can buy their digital goods from outlets other than Google Play.
So how do the three stores compare, and where should you turn if you have an Apple or Android device? Here's a little guide we put together.
We've established that music can be purchased on iTunes, but if you go to the music sections of Google Play or Amazon from your computer, you can also buy your music there and then easily move it onto your iOS device such as an iPhone or iPad. Depending on the song, one store might be cheaper than the others.
Both services will hold your music in the cloud, which you can access by downloading the Amazon Cloud Player app or by going to music.google.com. Additionally, you can download the files you bought, add them to your iTunes library and move them to your device that way.
With Android, you can buy music directly from the Google Play store and the Amazon Cloud Player app. You can also add iTunes-purchased songs to Android devices in various ways, including connecting the device to your computer and transferring the files.
Apple users have iBooks, of course, but they also have access to Amazon books via the Kindle app and Google's offerings through the Google Play Books app. You can't use either app to buy books -- you'll have to do that through the stores' websites -- but you can download the books to your device and read them just fine.
So where should you buy books? If you want to save money, choose on a case by case basis, using the store that has the lowest price each time. But if you want to be able to read your book on practically any device, including your computer, you may want to buy from Google or Amazon. Both offer apps that let you read your books on your computer, regardless of whether you have Internet access.
If you have an Android device, you of course get access to Google Play Books. You can also download the Kindle app and buy Amazon books straight from there. Unfortunately, iBooks are available only on iOS devices.
If you're looking for movies, you can buy them from both iTunes and Amazon -- which you can watch using the Amazon Instant Video app that is available for the iPad. Both offer a vast catalog of films, including some with subtitles available, but in general, you may want to stick with iTunes.