It doesn't matter what app you use. Filters aren't much of use too.
The problem is 95% of people who are "willing" to find language partner are not determined enough.
Most of them just add you to friends and thats it. Some exchange a few messages with you.
Learning language isn't their priority or they are too shy to communicate on regular basis.
Bottom line, if you are lucky 1-2 out of 20 might become a real language exchange partner..