Most Helpful Girl
It's not just girls, guys do it too, I'll message guys cute jokes, and compliments and a lot of the time they do not respond. It could be because they decided after swiping right they weren't really interested, or they don't check the app very often or they don't really want to talk to anyone in the first place. Sometimes I swipe through tinder just because I'm bored even if I'm not looking to talk to anyone
Most Helpful Guy
I find a lot of the people on these apps only reply if they like your photo, they don't care about what you like or much about the person, you are either flick left or right, a 1 second decision based on the photo they see and how they feel St that moment. If people are that shallow to flick people aside in a second then they are not worth being your friend or dating, as at anytime they could just flick you out of their life. Real friends and couples get along because they like each others personalities, the way they talk and laugh, etc, looks do matter to most people, not just for themselves but as they care what others think of who they are with too. Most dating is fake anyhow, people dress up tell lies get together see the truth and well make other choices.
A lot of people don't reply as they don't have time, or they are message people they chat to already or even as they left the app.
Many reasons really. Be aware some apps are fake too. There are hundreds of them of play store where they are totally fake profiles, and have staff pretend to be these people, read the terms, it will tell you there if they have fake profiles as many do this to get people to talk and join and once they pay they are screwed.
Try meeting real people, go cafes, library, Concerts, clubs, work etc find real people if they like you in person then that's far better than a man sitting behind s hot chicks photos.