From PC World:
Amazon offers the greatest number of options for accessing content; iTunes has the largest amount content but lacks streaming options.
With the upcoming launch of the Nexus Q, which lets you stream Google Play content to your TV or stereo, Google will compete more directly with Amazon and Apple in a media-store melee where price is taking a backseat to how and where consumers can play what they buy.
Using both a computer and a tablet linked to each store, I checked out the online media markets run by these Internet behemoths. I used a Kindle Fire for Amazon’s music and video stores, an iPad for Apple’s iTunes, and an Android tablet for Google Play.
Apple Has the Most Content
I found, first of all, that Apple continues to have the biggest catalog of music and video offerings–more than 28 million songs and 45,000 for-purchase movies as of April, and more than 85,000 TV episodes as of last October.
Amazon’s MP3 store hosts more than 20 million songs, and an empty search of its Instant Video store indicates that it has more than 52,000 movies. It’s difficult to gauge the number of TV episodes available there; the search shows more than 9000 TV titles, but titles may encompass entire seasons in some instances.
Google is far less specific about the size of its catalog, but it clearly trails the other two. Publicly, Google says only that it has “millions” of songs and “thousands” of movies and TV shows.
Varying Pricing Models
Prices for current releases were the same at all three services: You can rent movies in standard definition for $3.99 each or in high definition for $4.99 each, or you can purchase them for $14.99 (standard def) or $19.99 (high def). In the music markets, current albums go for $10.99 apiece and singles for $1.29 apiece.
Nevertheless, I found considerable variation in the pricing of older movies, TV shows, and music. Google Play, for example, offers a free song every day (presumably to attract you to the store).
Amazon Prime members can stream thousands of movies and TV shows to a computer, a Kindle Fire, an XBox 360, or another supported device free of charge: I used the service on a Kindle Fire to watch the 1954 version of Sabrina, which costs $2.99 to rent and $9.99 to buy on Google Play and on iTunes. Not all devices that support Amazon Instant Video also support Prime Instant Video, however. For example, my TiVo DVR, which offers access to Amazon Instant Video, can’t stream Amazon Instant Prime content.
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