DNS is a fundamental building block of the internet, so every device has support for it built-in. You don't need to download an app to manage your DNS, but you need to read up on where you can configure the DNS settings on your system. Mostly it's a section in network settings.
The IP addresses of our DNS servers you may use in your configuration:
daan.oblak.be - 89.147.108.180
dana.oblak.be - 93.95.231.108
These DNS servers support DoT (DNS over TLS), which is a relatively new improvement. Read more about it on the DNSCrypt website.