Between the first quarter and second of 2013, tablet shipments were down 9.7%, according to research firm IDC’s latest quarterly tablet tracker. That's one of the first times since the launch of Apple’s iPad in 2010 that tablet sales declined from one quarter to the next.

Oddly enough, Apple itself is primarily to blame. Sales of the iPad declined in Q2 2013 to 14.6 million, down from 19.5 million in Q1 and down from 17 million in Q2 2012. You could argue that an aging lineup was to blame, although the latest iPad and the iPad mini both debuted last October, just nine months before the end of the second quarter.

And while the iPad slumped, Android tablets charged ahead. How'd that happen?

IPad? What iPad?

Apple announced the first iPad in the spring of 2010. The second came in the spring of 2011. The third in spring of 2012. The fourth and its little brother, the iPad mini in late October 2012.

Apple's decision to launch a new full-sized iPad was a big surprise last fall. The third-generation “New” iPad was only a little more than six months old, and the fourth generation update disappointed many who'd plunked down good money for a tablet that was completely overtaken just a half year later.

Apple also reset its timeline for future iPad announcements. The spring announcement was no longer tenable, unless Apple all of a sudden decided it was going to act like Samsung and release a new version of its product lines every few months. That would be a distinctly un-Apple-like turn of events. So, the newest versions of the 9.7-inch iPad and its 7.9-inch Mini sibling are thought to be later this year, in time for the holiday shopping season where gadget sales go through the roof.

Overall, IDC predicts 45.1 million tablets were shipped in Q2 2013. The 9.7% decline from Q1 this year means that manufacturers shipped about 4.37 million fewer tablets between the first and second quarters of the year. Considering that iPad sales dropped by more than that—4.9 million units—something else really picked up the slack.

That something else was Android.

Tablets Still Surging, Android Doing The Lifting

Shift focus for a second to year-over-year sales. In the second quarter, tablets shipments grew year-over-year by 59.6% from 28.3 million in Q2 2012. That’s an increase of 16.8 million tablet units. Over that same period, iPad sales fell by 2.4 million units. With the iPad lagging yet the tablet sector still growing, the slack was made up by Android.

Android tablets accounted for 28.2 million shipments in Q2 (Windows 8 and Windows RT account for a combined 2 million shipments), representing 62.6% of the tablet market. That's almost a complete flop from the Q2 2012 market share when Apple’s iPad controlled 60.3% of the market. Android tablets shipped nearly as many total tablets in the second quarter of this year (28.2 million) as total tablet shipments this time last year (28.3 million including 19 million iPads). 

Wait, wait a minute here. What happened? Wasn’t tablet dominance supposed to be the divine right of Apple’s iPad and its iOS mobile operating system?

How Android Took Over The Tablet Market

The first Android tablet that was not an overgrown smartphone (which classifies any tablet that ran on Android version 2.3 Gingerbread or before) was the Motorola Xoom, launched in February 2011. It was the first (and one of the only) devices that ran on Android 3.1 Honeycomb, which was supposed to be Google’s split of its mobile operating system designed specifically for tablets.

It was awful.

Despite impressive hardware, the Xoom was devoid of consumer-friendly features, was too expensive ($800 and $600 with a two-year Verizon contract), buggy and slow. The Xoom was a disappointment for anybody that wanted to escape the iPad-centric world of tablets and get a true Android tablet.

Compounding the problem, there were really no Android apps optimized for tablet performance. While Apple has steadily enticed developers to build iPad-specific apps (with 375,000 at last count earlier this year and growing), the Xoom and other Honeycomb tablets had to make due with smartphone apps that awkwardly fit on larger screens.

Eventually, Google and its Android manufacturing partners got their act together. Google released Android 4.0 Ice Cream Sandwich, a version of the operating system that combined the best features from version 2.3 Gingerbread and 3.1 Honeycomb, added new polish, features, performance and functionality and made decent Android tablets possible. Some quality offerings eventually came to the table, notably the Nexus 7 by Asus released in the summer of 2012 running Android 4.1 Jelly Bean and the Nexus 10 by Samsung (and an updated Nexus 7) in the fall.

Android tablet manufacturers also recognized that they could beat Apple on price, undercutting the iPad with tablets at an attractive $199 (as Amazon did with its Kindle Fire tablets and Asus/Google did with the Nexus 7). Samsung, armed with a version of Android that worked well on tablets (and allowed developers to target their apps at bigger screen sizes) continued to release a plethora of slate offerings in both its “Note” and “Tab” product lines. 

The result? Android tablets that people actually want to buy at prices they can afford. As Apple insists on still charging a premium for its smartphones and tablets, it gave Android the opportunity to carve out a wide swath of the market, from the poorest low-end tablet on the market to very nice options such as the new Nexus 7 that Google announced last week.

Whither … Apps?

Tablet specific apps continue to be a problem for the Android ecosystem.  Google has no specific number it can point to and say, “we have this many tablet apps” the way Apple can do with the iPad. That is a problem. Apps are big selling points for mobile devices and without them the Android tablet ecosystem is handicapped.

It is not quite as bad as people often make out though. Google has made it fairly easy ever since Android 4.0 Ice Cream Sandwich for apps to fit a variety of screen sizes using the same basic design. Google is also now giving Android developers ways to build responsive apps that automatically adjust to screen sizes and created a feature in its new Android Studio integrated developer environment to target different screen sizes. Google is essentially saying that Apple can continue to count tout iPad-specific apps; Google will just help developers make apps that work everywhere.

As an individual manufacturer, Apple is still the largest single tablet maker. But it is looking distinctly isolated amid the same kind of Android Army has dominated the fields in the smartphone market.