Tech issues - eyefi

Just bought an 'eye-fi mobi' card to use with my Nikon, as my camera is very underused. I'm having real issues getting the eyefi card to stay connected to my iPhone, the connection keeps dropping off. When it does connect it says 45 minutes, I'm assuming that's how long to download, but can't see if there is something I need to do to activate it, if I'm doing something wrong I can't figure out what it is.... Anyone have experience dealing with these cards? *feeling frustrated! *