If you are really interested in selling and getting the best price find a company that specializes in selling tech companies. In the space I operate on dhcapital is one who handles some of the technology space and would likely understand an app. For multiple - not sure what an app gives now a days my guess with higher borrowing costs is it would be a multiple of profit and not revenue. Other options are seeing if there are any larger dating sites who may be interested. If you are not getting direct unsolicited offers to sell and don’t want to go through another party to sell use your profit margin to do some targeted ads and try to build brand to get noticed by a larger company.