[WheelsAtLarge]

You have to grab their attention via other means. Think about what other points of interest your users have as individuals. Cater to that interest and once you have enough people then you introduce the dating app service. Else you can visit your target audience where they gather and tell them about the service and give them an incentive that will keep them interested until there enough people to make the service useful. Such as a 2 year free membership for the first 5000 users. You can also partner with another service that has the users and would want dating as a new service.

Think about what new communities are appearing on the net and create a dating service for them. What new interest have you seen growing lately?