How promote app in competition with dating apps like Tinder?

I made a simple web app which allows users communicate in close geo area, you send a message and it will visible for all users around you in 5km. But when I started thinking about promotion realise that i have to use the same targeting as datings apps and cost per click is quit high. From my rough estimation i should spend 100-200$ every day on ads to make my app live and it only for one city. How it could be solved in other way?