According to a recent report by ABI Research, Android tablets have taken 20 percent of the market from Apple’s iPad over the past year. However, analyst Jeff Orr says that no single tablet has yet been able to challenge the iPad, which might be caused by the high prices of Android tablets.

Orr also pointed the fragmentation of the Android operating system which is hindering overall app development, as there are three different versions of the OS that can be found on different tablets (Froyo, Gingerbread and Honeycomb). App developers have to pick a specific version or may delay based on the market potential.

Android will presumably still take Apple’s market share until 2020, but Apple will still have 60 percent of the tablet market by then because of its price and huge app market.

Check out the full report.