SBK is a safe mobile app to play betting on. Smarkets, the parent company to SBK, is licensed and regulated by the UK Gambling Commission and Malta Gaming Authority. All users personal and banking information is secured through SSL data encryption.
As SBK is a sports betting company, they are serious about responsible gaming. In their Help Center, there is a section devoted to promoting responsible gambling and how to set deposit limits if you feel your hobby is getting out of control.