DropConf is an on-demand conference calling application that allows users to pay per conference call, offering a more cost-effective alternative to traditional monthly fees. The service uses Twilio's telephony capabilities and was created by the founder of MoFuse, who is now looking for a new owner to bring it to market. This innovative approach aims to cater to small businesses and freelancers who may not need frequent conference calls, providing a flexible solution for those occasional needs.