SAN MATEO, CA – As expected, worldwide tablet shipment growth slowed in the second quarter according to preliminary data from International Data Corporation. Worldwide tablet shipments finally experienced a sequential decline as total volumes fell -9.7%.

The 45.1 million units shipped in the quarter was up 59.6% from the same quarter in 2012, when tablet vendors shipped 28.3 million devices.

Lacking a new product launch in March to help spur shipments, Apple's iPad saw a lower-than-predicted shipment total of 14.6 million units for the quarter, down from 19.5 million sequentially. In years past, Apple has launched a new tablet heading into the second quarter, which resulted in strong quarter-over-quarter growth. Now, Apple is expected to launch new tablet products in the second half of the year, a move that better positions it to compete during the holiday season. Meanwhile, the other two vendors in the top 3 also saw a decline in their unit shipments during the quarter.

Samsung shipped 8.1 million units, down from 8.6 million in the first quarter, although up significantly from the 2.1 million units shipped in the second quarter. Asus shipped a total of 2 million units in the second quarter, down from 2.6 million sequentially.

"A new iPad launch always piques consumer interest in the tablet category and traditionally that has helped both Apple and its competitors," said Tom Mainelli, research director, Tablets at IDC. "With no new iPads, the market slowed for many vendors, and that's likely to continue into the third quarter. However, by the fourth quarter we expect new products from Apple, Amazon and others to drive impressive growth in the market."

Not all vendors experienced a slowdown during the quarter. PC stalwarts Lenovo and Acer both re-entered the top five this quarter. Lenovo continued to make headway into the world of mobility and for the first time had shipments surpass the million unit mark in a quarter, shipping a total of 1.5 million devices. This was up 313.9% from a year ago and enough to capture 3.3% market share. Rounding out the top 5 was Acer, which shipped 1.4 million tablets for 247.9% year-over-year growth and an increase of 35.4% over the first quarter of 2013.

"The tablet market is still evolving and vendors can rise and fall quickly as a result," said Ryan Reith,pProgram manager for IDC's Mobility Tracker programs. "Apple aside, the remaining vendors are still very much figuring out which platform strategy will be successful over the long run. To date, Android has been far more successful than the Windows 8 platform. However, Microsoft-fueled products are starting to make notable progress into the market."

Top Five Tablet Vendors, Shipments, and Market Share, Q2 (in millions)

Source: IDC Worldwide Tablet Tracker, August 5, 2013.