Is there an Intelligent/Location Network Connection App?

Edit: I swear I was posting this in the Apps forum. Sorry, can a moderator move it please?

Hi,

I'm trying to figure out if there's an App out there that would either:

1) Automatically switch off my 3G Data and turn on my Wifi when I'm at a "Home" or otherwise preset location that I know I have a strong wifi connection to reduce my 3G data usage...

2) Have a similar setting that I could do with one or two touches rather than having to go into Settings, Network, etc and individually turn on Wifi and turn off my 3G data.

Again, ideally this would be based off my location so I wouldn't have to do anything, but I wouldn't mind pressing one or two buttons.

Anyone that's used a Blackberry OS probably remembers the one-button shortcut to pull up your Manage Connections where you can enable or disable all your connections in a click.

Thanks.

 

It's been mentioned/suggested that people without the unlimited AT&T data plan turn off their Cellular Data when they use Wifi, perhaps because when it goes into sleep mode and the screen locks that it's turning off the Wifi and going back to Cellular Data, which would be a problem if you're streaming music.

Basically, I want to forcibly ensure that I'm only using Wifi on my iPhone when I'm at a certain location to keep my 3G data usage down.