Didn't expect this comment to get downvoted. This is just a comparable number that is closest to the definition in title we can get. There is no information on

Didn't expect this comment to get downvoted. This is just a comparable number that is closest to the definition in title we can get. There is no information on the "first two hours signup" in a social network app launched by a large technology company that has the means to push their existing user to signup the new service. There is nothing implied.