Google’s smartphone and tablet marketplace, the Android Market, has reportedly hit 400,000 applications, adding another 100,000 apps in just four months, a new report from app tracking specialists Distimo reveals.

The Android Market has doubled in size since April 2011, helped by the publishing of an increased number of free applications. According to Distimo, free applications make up roughly two-thirds of all available apps on the platform, having grown month over month from 60% in April to 68% at the end of December.

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Distimo offers a direct comparison to Apple’s App Store growth, noting that Google needed an additional two months to reach the 400,000 mark. With Apple reaching 200,000 apps in 22 months and the Android Market requiring 31 months, the Google marketplace needed only four months to pass 300,000 apps, whilst Apple needed eight months.

It continues:

Moreover, the gap between the 300K and 400K milestone is also smaller for the Android Market than for the Apple App Store for iPhone, 4 and 7 months respectively.

According to Distimo, the Android Market is also closing in on another milestone; 100,000 active developers. As it stands, each developer publishes four applications on average, falling from an average of five a year ago. The company says that the number of apps in the Android Market were active at the time and excluded removed or deleted apps.

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