iPad is top selling tablet, but Android now most common tablet OS, says IDC

More tablets were shipped during January and March this year than the entire first half of 2012: 49.2 million units during the three-month period, according to IDC. The analyst firm’s Worldwide Quarterly Tablet Tracker was published Wednesday and it shows that tablets continue grow at a rapid clip. Every major tablet maker saw large gains in shipments during the first quarter — and one of the notable results of that is that Apple’s(s AAPL) overall share of the tablet market is decreasing.

Apple is still the world’s largest tablet seller; it shipped 19.5 million in the last quarter, up from 11.8 million the same quarter a year ago, according to IDC and its own numbers released earlier this month. That’s an increase of 64 percent. Its No. 1 mobile competitor, Samsung, saw its shipments¬†grow even faster, from 2.3 million tablets a year ago to 8.8 million in the latest quarter. Rounding out the Top 5, Asus and Amazon(s AMZN) also more than doubled their tablet shipments from a year ago. Microsoft,(s MSFT) which did not start selling tablets until October 2012, shipped¬†900,000 Surface units between January and March.

The overall growth in tablets means Android is now the most popular mobile OS in tablets shipped during the quarter; a year ago it was on 8 million of tablets shipped worldwide, compared to the 11.8 million iPads. This past quarter saw Android shipped on 27.8 million tablets that were shipped and 19.5 million iPads and iPad minis.

All this does not mean doom and gloom for the iPad. Apple’s tablet sales continue at a rapid clip, increasing every quarter — faster than the iPhone right now. And while its overall share of tablet shipments may be slipping, it’s still selling more than double the number of tablets each quarter as its closest competitor, Samsung (see chart below).

IDC tablet tracker q1 2013