I'm trying to do a project , Can you please tell, How can I make an android app that detect?

Finding animala/insects by a phone app is impossible. Just think about it, if you wanted to do that you would need a GPS locator on all insects or in your case mosquitos, then from the phone track down the mosquitos. There might be a way however but you will nees to study the mosquito deeply and find out what makes it so different from other insects then use the app to locate that difference. It's hard to explain and hard to make, but good luck. If this ever becomes a app, then please link it. Looking forward to it. :)