Snapchat lawsuit: Sisters sue founder Evan Spiegel over bikini photos

Sarah and Elizabeth Turner claim they agreed to pose for free in a bikini to promote app- now worth $10 billion- effectively becoming 'slut' face of Snapchat

Sarah and Elizabeth Turner in the original Picaboo snaps

Two sisters have sued Snapchat, the app which allows users to send photographs that are automatically deleted within seconds, arguing it has damaged their reputation.

Sarah and Elizabeth Turner claim they agreed to pose in a bikini for Snapchat founder Evan Spiegel as a "favour" to help promote an app he was working on at the time called "Picaboo".

"Picaboo" later turned into Snapchat and the blonde sisters effectively became the face of the controversial app, which is often used for sexting. The Turners argue the photographs come up if you Google "Snapchat sluts" and say this has led to serious reputation damage and a violation of their privacy rights.

In the lawsuit filed earlier this week, the sisters, aged 18 and 19 when the photographs were taken, note they did not receive financial compensation and agreed to pose exclusively for “Picaboo” iPhone app in what Spiegel and co-founder Robert C. Murphy initially described as a "school project".

They also claim the photographs were edited to make it look like one of them was naked and what was meant to be an innocent day at the beach turned into an overly sexualised photoshoot.

This isn't the first time Spiegel finds himself in hot water. Earlier this year, he was forced to apologise for a series of e-mails with references to drug use, drunk sex and misogynistic behaviour while he was a student at Stanford university.

Snapchat was recently valued at $10 billion after renowned venture capital firm Kleiner Perkins Caufield & Byers agreed to pump $20 million in the start-up in new investment round, according to reports citing sources familiar with the matter.

Spiegel initially rejected a $3 billion cash offer from Facebook.