Figures from research firm Strategy Analytics show that while Apple still dominates the tablet market, devices powered by Google’s Android platform are beginning to gain ground.

According to the company, in the fourth quarter of 2011, 15.4 million units were shipped powered by Apple’s iOS, compared with 10.5 million for Android, giving market shares of 57.6 percent and 39.1 percent respectively.

In total, 26.8 million tablets were shipped during the three months, up from 10.7 million in the comparable period in 2010 – at which point Apple had a 68.2 percent market share.

In a statement, Peter King, director of the research firm, said that: “Apple shrugged off the much-hyped threat from entry-level Android models this quarter.”

The company said that Microsoft “captured a niche 1 percent” share during the period, noting that “the upcoming release of Windows 8 this year cannot come quickly enough for Microsoft, so its hardware partners can start competing more effectively in the tablet space.”

Less positively for competing vendors, including RIM, market share for the “others” category fell to 1.9 percent from 2.8 percent. Due to growth in the market, this represents an increase in shipments to 500,000 from 300,000.