As usual for this type of app, Flirchi is completely free, but many of its features aren't. To access some of them you have to pay. One of the most interesting paid features is the ability to find people close to you, which is free on other apps.
You can set filters for the kind of people you're interested in. Only men, only women, a specific age range, a particular city, etc. There are plenty of options available.
Flirchi is a pretty mediocre social network for hookups: it doesn't offer more or better features than any other similar app, and it's used by a considerably smaller number of users. At least for now, there are plenty of better alternatives if you want to meet people with the same interests.