All reports now suggest Apple will introduce its second-generation iPad in the second quarter of 2011. We can expect this to host a much faster processor, a camera and to be thinner and lighter than the current edition, but it enters a far more challenging market.

This is because competitors are not sitting still as they attempt to do their best to ensure that -- when it comes to relative tablet market sales -- 2011 won't be like 2010.

HP, RIM, Amazon, Samsung and many others plan next year to release iPad-competing tablets powered by different operating systems, including webOS, Android and BlackBerry OS.

There will be lots of choice in this brave new tablet world.

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This means that when Apple's iPad 2.0 hits stores it will be facing far more competition than it did this year. That's because competitors delayed plans to enter the tablet market as they waited for Apple to lay down the blue-print for success in this new industry.

However, that Apple has already defined the tablet industry means consumers will be asked to choose between an array of devices in either 7- or c.10-inch form factors, equipped with touch screens, cameras, and app stores. There will be lots of almost identical devices.

Almost every tablet scheduled to appear in 2011 will be connected to some form of App Store. BlackBerry, tablets running Windows 7 (or the mobile equivalent), Android-powered and webOS-powered tablets will all invoke the power of the app.

Perhaps Apple saw this as a point to which we were going. Perhaps executives predicted the app would be the key to unlock continued success in the tablet market.

However, if they did they kept this close to their chest -- who else can recall WWDC 2007 when Steve Jobs disappointed developers when he urged them to create Web-based apps for the iPhone? 

"Developers and users alike are going to be very surprised and pleased at how great these applications look and work on iPhone," said Steve Jobs, Apple's CEO.

"Our innovative approach, using Web 2.0-based standards, lets developers create amazing new applications while keeping the iPhone secure and reliable."

This strategy soon changed to embrace the notion of curated third-party apps for iOS (as it became) family devices.

Apple now boasts in excess of 250,000 apps are now available via the iTunes App Store. It also boasts the most active developer community, many of whom enjoy the 70/30 revenue split Apple offers, along with the opportunities to host sundry ads and in-app purchases within their offerings.

Apple continues to develop its developer community, though it has scored a few own goals, developing a reputation for censorship and rejection of some apps; a reputation for control, and stirring some bad feeling when it decided to prevent introduction of apps such as Google Voice and preventing easy export of Flash apps into iOS-ready variants in its multimedia spat with Adobe.

Apple's ability to listen to its developers came clear this month when the company loosened-up its developer agreement to allow for inclusion of ads from other networks and development of apps using tools not supplied by Apple (so long as these didn't require download of additional code).

These steps went a long long way to erode competitor's arguments that Apple is too controlling, as did the move to introduce new developer guidelines written in plain English.

These things matter, because ultimately, the battle for the tablet industry -- just as in the battle for the mobile OS business -- seems increasingly to hinge not just on introduction fo fantastic and amazing whizz-band products, but also on the evolution of a strong third-party industry of app developers. Which means sales.

At present that battle is defined as Apple versus Android. Amazon is expected to introduce its own App Store for Android devices, including its own Android-powered tablet; BlackBerry and Microsoft are already investing in subsidies for key developers to ensure they introduce apps for their devices.

When it comes to Apple today, developers are already looking at a market that's growing fast. It isn't really a surprise developers achieving success in the App Store market are also developing apps for Android OS -- this is something that constitutes firm business sense.

In future, developers are already curious if Apps really will be enabled using the newly-discovered App Framework on the iOS 4.1-based Apple TV.

They are also curious as to what Apple will put inside iPad 2.0.

Apple meanwhile is watching the competition to ensure that what it does put inside iPad 2.0 enables it to claim to offer a more compelling product than available elsewhere.

This is fine, but the future of the smart tablet will be determined not by Apple, nor by competitors or consumers, but by third party app developers and the continued evolution of a massive market of multiple niche apps.