The Kindle store's ever-increasing inventory -- up to 1,404,731 digital items for sale as of May 30, plus e-books available as OverDrive loans from compatible libraries -- has padded out the value of the Fire. Software updates have added options like easier sharing of text excerpts on social networks, but they haven't made it much easier to read files published in other e-book formats.
But the greatest failing of this e-reader is the original sin of the e-book business: Almost all the titles you buy come with "digital rights management" restrictions that lock them out of competing readers. That's a distinct contrast to Amazon's excellent MP3 store, which sells standard music files you can download on the device of your choice -- or stream from Amazon in the Fire's Cloud Player app.
The Fire has also grown as a video-playback device, thanks to content deals that have added prime-time shows from Discovery Communications and Fox, among others.
Scores of would-be iPad rivals have emerged on the tablet market, but Apple is still steamrolling the competition.
