Skype claims to have hit 2 million downloads of its ‘Skype for iPhone’ software since the mobile VoIP client debuted on Apple’s App Store on 31 March. Writing on the VoIP company’s official blog, Skype’s Peter Parkes said it is currently seeing an average two to three downloads a second. The 1 million milestone was reached within two days of launch, establishing the software as one of the fastest-downloaded iPhone apps ever. Parkes added that many of those downloading the application were new Skype users. He noted also that Skype was “working tirelessly” on a new release of the iPhone software.

The current version of Skype for iPhone can only be accessed via Wi-Fi hotspots and not via standard mobile networks, but recent reports suggest that some mobile operators are considering blocking Skype’s VoIP traffic over their networks. Skype already offers a version of its software for Microsoft’s Windows Mobile and Google’s Android platform, while a version for the BlackBerry is expected next month. Meanwhile, the New York Times reported over the weekend that Skype founders Niklas Zennstrom and Janus Friis have contacted several private-equity firms over buying back the company from eBay. The online auction giant bought the company in 2005 for US$2.6 billion, but wrote down the value of the purchase in 2007. Skype is currently valued at around US$1.7 billion.