I have been using reddit to do user research for while. Basically this process involves finding threads where users are discussing topics related the the research I am doing. From there, I message users and ask if they are willing to give feedback on an idea. This app automates a portion of this work by gathering these users and sending the message to each of them. From there, I continue the conversation in reddit messages. This approach has been quite successful, I can normally find a few dozen users who are interested in the idea I'm researching.