Why the heck would I want to open a port to accept http connections to the wild wild web on my phone? Servers are constantly being probed and I can't imagine I'

Why the heck would I want to open a port to accept http connections to the wild wild web on my phone? Servers are constantly being probed and I can't imagine I'd want to manage a firewall from my phone. Then there's data plans... Oy vey!