I didn’t realize it until I spent yesterday at a family member’s house that when you’re connected to WiFi with your iPhone, there’s a different indicator than the one when you’re connected to AT&T Edge network. The Edge network is a tiny ‘E’ up in the status bar. The WiFi indicator is the small inverted pie shaped strength meter.
So while I thought I was connected to my local LAN here at home, I really wasn’t. No wonder things were so slow.
My WiFi is secured with a WEP password, which you are asked for when connecting to a secured network on the iPhone. However, the default password type that it asks for is a text password. I unwittingly entered in my router’s HEX password, which doesn’t work as a text password.
You get no warning from the iPhone when the password is incorrect, and it happily continues on with no real connection. Of course it “remembers” this non-connection and doesn’t prompt any more when in this WiFi area.
How I Fixed it
I manually connected to my network by specifying it in the WiFi Settings, “Other…” option. I entered the SID, and chose “WEP hex or ASCII” instead of the default “WEP Password” and entered in my 10-digit hex password. Enter your password carefully by holding your finger on each character you type so you see it expand before letting go.
Side note: This is the “careful typing” method I’ve developed over the past few days. If you hit the wrong character without lifting your finger, you can slide over and get the right one. That helps a lot when typing into a password field with no visual feedback.
Those settings replaced the bad one and now it works like a charm.
If you’re at home in your secure network and you see the “E” Edge network icon at the top, you’re not connected to your WiFi Network.
Don’t get caught with an imaginary WiFi connection. It’s much slower than an actual connection. 
