That's the page for the Motion utility. It's listed somewhere in there that it has 'control over simple web interface', so that fits what you're after pretty well.
If you have any programming experience maybe you could write a script which monitored the network status, and when your phone attaches to the network (you've arrived home (or whatever arrived home condition you wanted)), it disables/stops the Motion service, and then when the phone goes out of range, restarts it?
http://www.lavrsen.dk/foswiki/bin/view/Motion/WebHome
That's the page for the Motion utility. It's listed somewhere in there that it has 'control over simple web interface', so that fits what you're after pretty well.
If you have any programming experience maybe you could write a script which monitored the network status, and when your phone attaches to the network (you've arrived home (or whatever arrived home condition you wanted)), it disables/stops the Motion service, and then when the phone goes out of range, restarts it?