Is there any way to find out the latitude/longitude of a place using IP address.
But the iphone is supposed to have an embedded gps chip, so I think you might use it to get this information.
Moreover, I think that with IPV6 you'll be able to use a given IP from multiple locations.
Assuming you're trying to find the position of someone/thing else, then generally no. There are a few exceptions, for when that IP address is registered to an individual business, which in turn list their full address in the whois record. You could then geocode that using a webservice (etc.) to get lat/long.
If you're trying to find out where you are, then you're probably better off using the built in GPS
ip2location.com has a number of resources (some of which are free) for doing this, including scripts and demo databases - but I'm no iphone expert so I don't know if they're of any use in that particular environment.
The IP address doesn't uniquely identify a location.
I know I get a lot of unwanted ads telling me about good times to be had in my location.
The problem is the location is wrong.
I use quite a good free api for that in my PHP projects: http://api.hostip.info/?ip=IPADDRESSTOLOOKUP
returls XML... not sure if this is of use to you! :)