"Now we're joining the Gmail team to accomplish a bigger vision -- one that we think we can better achieve with Google," said Dom Leca, chief executive officer of Sparrow, in an announcement posted on the company's website Friday.
No financial details of the acquisition were disclosed, reported Xinhua.
Sparrow said its applications will continue to be available for the time being, but they do not plan to release new features for the Sparrow apps anytime soon, said the company in an email to its users.
Sparrow offers email client service, which is formally called mail user agent. It is a programme used to access and manage a user's email.
The company launched its application for Apple's OS X operating system in October 2011 and its app for Apple's iOS mobile operating system in March, both of which have quickly gained popularity for their simple and efficient service.