Andy Rubin, VP of Engineering at Google, tweeted that “over 300,000” Android devices are being activated every day, following reports that the stellar growth of the mobile OS has slowed somewhat in recent weeks. The figure puts Android on a par with Symbian OS, the smartphone market share leader by volume, and ahead of Apple’s smart device range, based on the figures most recently provided for the other platforms. AppleInsider noted some discrepancies in the figure: when Google announced the Nexus S smartphone on Monday, a figure of 1.5 million devices per week was given, which is closer to the 200,000 Google claimed in August 2010 than the 300,000 claimed now. The entry for the Nexus S on the official Google mobile blog, attributed to Rubin, also reiterates the 200,000 figure. The figure of 275,000 has been given for daily iOS device sales.

Unsurprisingly, there has also been some debate about how the figures are counted, with the vendors themselves doing little to clarify the position. While both Android and iOS results will include smartphones and tablets, the Apple number could also include iPod Touch users, while the Android figures may omit devices powered by a variant of Android that does not support Google’s services, such as China Mobile’s Ophone. Either way, there is little doubt that Android has seen stellar growth in recent years, positioning it as the biggest threat to Symbian OS in the smartphone mass-market. In a recent blog post, analyst firm Strategy Analytics noted that Google’s growth has been driven by “strong support from its many partner vendors.” In the third quarter of 2010, Samsung became the largest Android device vendor off the back of its Galaxy S device, and HTC is also especially active – the company is reportedly preparing to triple the number of devices it ships. Android shipments are also being driven by LG Electronics, Motorola and Sony Ericsson.