• by Gavin O'Malley  @mp_gavin, July 14, 2014

Fighting for survival in a saturated social messaging space, Secret just raised another $25 million.

Participants in Secret’s Series-B financing round included Index Ventures, Redpoint Ventures, Garry Tan and Alexis Ohanian, SV Angel, Fuel Capital, and Ceyuan Ventures.

Also this week, the start-up is launching “Secret Collections,” which gives users a daily dose of the most popular secrets being circulating around the network.

Secret users can subscribe to various “collections,” and then automatically receive new secrets from that collection in their “explore stream.”

“This is a first step in giving users more control over their experience on Secret,” the company explained in a Monday blog post.

Secret also debuted a feature so users can now join the network using their Facebook Login on Android and iOS.

“Facebook Login gives any user the option to (completely anonymously) connect Secret to Facebook and populate your stream with Facebook friends,” according to the company.

Presently, the most popular social networking niches among young users, anonymous and ephemeral messaging have quickly become crowded categories.

Along with Secret, consumers (and investors) can choose from Snapchat, the most popular disappearing messaging service, according to Forrester, Whisper, PostSecret, sixbillionsecrets and Slingshot -- Facebook’s very own disappearing message service.

Investors continue to place their bets. In March, for example, Whisper raised nearly $30 million -- and just six months after its previous investment. Further illustrating the strength of secretive sharing, Snapchat famously rebuffed a $3 billion buyout bid from Facebook, last year.