Traditional dating sites don't allow you to search for girls you know, unlike the apps. There are a couple reasons why they do this. First, it would make it a lot easier for them to sell their services to you, which might mean they would become a lot more successful and more popular. Second, if you use a dating app to find a girl, that means you are also spending money on a service that is also very important to you. As you will see below, it's not always a bad idea to have an app that helps you find girls you really want, instead of relying solely on a dating site.