NEW YORK (MainStreet) -- When Steve Jobs, the former CEO of Apple, introduced the iPad tablet in the beginning of 2010, no one could say for sure whether it would be the company's biggest success or just an over-hyped failure. By the end of the year, though, 15 million iPads had been sold, compared with 2 million tablets sold by other brands. Still, by March of this year there were more than 100 different tablets on sale.

In a very real sense, the success of the iPad attracted some of the biggest names in the technology world to try their luck in the burgeoning market, but only a few ended up with even a fraction of the sales Apple's ( AAPL) device enjoyed, forcing many companies to rethink their investments in the tablet area.
iPad
Apple is winning the tablet war and sending many wannabes to the tablet graveyard, including these five once-hyped products.

There are certainly tablets that have shown a greater potential to challenge the iPad, including Amazon's ( AMZN) Kindle Fire, but this is only after several have come and gone or failed to make it to the market at all. We decided to memorialize some of the most notable failures in the tablet market from the past two years to make sure others learn from their mistakes.

H-P TouchPad
The TouchPad was only on sale for a little more than a month this summer before Hewlett-Packard ( HPQ) that it would be discontinued. Looking back, it seems foolish to think H-P could charge the same price as the iPad for the TouchPad -- even though the device ran on its own specific WebOS operating system -- without all the apps available on Google's ( GOOG) Android and Apple's iOS devices. H-P had highlighted WebOS as a strength, focusing on the system's multitasking and browsing capabilities, but ultimately consumers were hesitant about spending $500 or more hoping the TouchPad's features would catch up.

That said, a strange thing happened when H-P announced the end of the product line in August, slashing the price of the TouchPad to just $99 for the cheapest model to cut its losses and sell off the remainder of its inventory: Sure enough, consumers rushed to snatch up the discounted devices, eager just to have a cheap tablet to play with, and some even tried to hack the tablet to get the Android operating system on there. Taken together, these events showed how wrong H-P was in its initial thinking for the product, yet they proved there is an appetite among consumers for an affordable alternative to the iPad.

Dell Streak 5
With the release of the iPad, Apple effectively defined a tablet as needing to be 10 inches wide. Other companies have played with this formula, putting out tablets with screens that were 2 or 3 inches larger and smaller, but Dell ( DELL) may have gone one step too far by trying to put out a tablet that was just 5 inches, half the size of the iPad.

As many pointed out after the Dell Streak 5 launched in mid-2010, the device was a little too big to fit comfortably in your pants or shirt pocket but too small for the quality multimedia experience (movies, games) that would justify the inconvenience of having to carry it around. It really didn't qualify as a smartphone or a tablet, and a little more than a year after it launched, Dell pulled the product from its Web site and began directing users to buy the 7-inch Dell Streak tablet instead.

Microsoft Courier
Even before the iPad was officially unveiled, Microsoft ( MSFT) was rumored to be at work on a tablet that would give Apple's product a run for its money. The tablet, known as the Microsoft Courier, was supposed to function like a " digital journal" with two screens side by side for a better reading and writing experience.

Rumors about the device's specifications and release date persisted for months until it was killed off in April 2010 with the goal of incorporating some of the technology from the tablet into other Microsoft devices in the future. Even now, it's hard to know if the idea of a foldable dual-screen tablet would have found a market. As nice as it is to replicate the feel of a book, this automatically eliminates those who want a tablet that can screen movies and other media.

Don't count Microsoft out of the tablet race just yet, though. As we reported, Microsoft recently demoed a version of Windows that boasts cloud capabilities, multitasking and other features particularly well-suited for a tablet device, whether it's one made by Microsoft or not.

Sharp Galapagos
If you haven't heard about Sharp's line of Galapagos tablets before, don't worry, you're probably not alone. The three tablets were on sale in Japan, not the U.S., and were supposed to be a steppingstone for Sharp to compete against the iPad in the Asian market. The tablets functioned as glorified e-readers, complete with their own digital bookstore and color screens, and ranged in size from 5.5 inches to 10.8 inches.

Sharp announced it would stop selling two of the three tablets at the end of last month due to lower-than-expected sales. All that remains now is the 7-inch Sharp Galapagos tablet.

JooJoo
Few products had as much trouble getting off the ground as the huge 12.1-inch JooJoo tablet from Fusion Garage. Before the product was even released, Fusion Garage was sued by a major tech blog that accused the company of lifting the idea from them. When the product did go on sale (at a starting price of $499) in early 2010, it got just 90 pre-orders, 15 of which were later returned. After several more months of dismal sales, the company discontinued the tablet in November.

Last month, Fusion Garage opened up pre-orders for a redesigned tablet called the Grid 10 with a smaller 10-inch screen that starts at just $299. Perhaps the company will have better luck the second time around.

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