One of dudesnude's best features is the pre-filtering system. On other sites and apps, you're forced to wade through the profiles of dozens of guys you're never going to be interested in. On dudesnude, you (mostly) ONLY see the guys you're likely to be interested in! You're also partially hidden from guys you're unlikely to want to respond to.
For this to work, you need to fill in the 'about you' and 'who you're looking for' settings.