Smartsteem

SmartSteem is a vote-selling/buying service with some lots of features. People can sell votes via SmartSteem and also buy those votes. There is a bid bot too called @smartsteem which is powered by SP delegations from other Steemit users and shares its profits with its delegators. Users can get whitelisted which helps in differentiating between quality of the users posts. In Smartsteem we can choose to vote based on the quality of posts of the user which helps in maintaining the quality of posts on Steemit. There is also a referral system in smartsteem. I have linked my referral link below.