The purchase and subsequent discontinuation prompted criticism from some tech sites, who were uncertain about the future of the apps. Due to this, they also announced that development of both of Sparrow's apps would be ended except for critical bug fixes. On July 20, 2012, Sparrow and Google jointly announced that Sparrow had been purchased by Google and the company's employees would be added to their Gmail team. In March 2012, Sparrow for iOS was released in the App Store. It also includes features such as drag-and-drop attachments, Dropbox or Box.net support for uploading attachments, Growl support, Gmail labels and keyboard shortcuts, as well as quick replies, threaded replies and easy switching between accounts. Sparrow currently works with Gmail and Google Apps accounts, along with other IMAP email accounts. Sparrow uses a simplified user interface reminiscent of Twitter clients such as Tweetie or iOS apps, as opposed to a more traditional email style such as Apple's Mail or Mozilla Thunderbird.