9:07 p.m. on September 25, 2012 (EDT)
A little common sense goes a long way. For starters he should have had the 10 essentials at a minimum, obviously he did not if he didn't also have a map and a compass., and should not have relied soley on his phone for navigation.
Now that being said:
I have an Iphone, and I do use it as my phone/gps/electronic maps/ backup flashlight/ and camera while on my trips. It works awesome, just as well as my Garmin Rhino. And No, you do not need cell service to use the gps functionallity. However, if you DO have cell service it greatly improves the accuracy. Without cell service it is just as accurate as any other handheld GPS I have seen. On long trips I carry a New Trent 9900mah battery pack that can recharge my Iphone about 5 or 6 times from 0 to 100%(i can also charge other things like my headlamp etc). I do not rely solely on my Iphone for navigation however, but it is quite a handy tool with gps and electronic topo and satellite picture maps. A gps is a tool to be used, no matter what it is in, whether its a smart phone or a stand alone handheld gps it is still a tool and is meant to aid in navigation but should not be the sole resource. A smartphone can be a valuable tool and multi purpose item (camera,gps,electronic maps,phone,text,email,weather,moon and celestial information, trailspace!, police scanner, flashlight, survival and first aid manuals, plant identification, and the list goes on and on)
I always carry a map and compass and use them primarily. I do use my iphone ocassionally to get a fix, but normally i keep it in airplane mode to conserve the battery. Using it this way I can make my phone battery last quite a few days. I do not always have cell signal on trips, but when I do have a signal at camp for the night I call my wife to check in briefly. If I have signal I can also send any unforseen changes in my itinerary to my wife.
Now, why did he call for rescue so soon? Probably because he wasn't prepared to spend the night. This time of year it can be deadly up in the High Peaks, with frequent rain fall and night time temps dipping below freezing. He was smart to call for help if he was not prepared, and by the sounds of it, he was not at all prepared and only had some basic gear with him.
Moral of this story is don't be an idiot. If you are going out into the backcountry, or even a hike close to home but in a seldom used area, carry the 10 essentials at a minimum. Be prepared to always spend the night out there, because you never know when something will go wrong. I am sure this guy wasn't planning to get lost, but lets face it, stuff happens. Hopefully this incident will teach the guy to be a little smarter when going out, and hopefully others learn from his mistake and don't head out unprepared. He is lucky the weather was fairly decent on that day or he might have died from exposure before they found him. It doesn't take long in temps around the freezing mark, with rain, to make a day hike turn into a life or death struggle.
And before anyone says it. Yes, i do go out into the backcountry to 'get away from it all, technology included'. My tarp is high tech, but i don't leave it at home, so is my head lamp, but i bring it too. I don't spend hours on the phone while hiking, or surf the internet,facebook(trailspace occassionally!) etc. A smartphone is a tool, use it in conjunction with your other gear basics and it complements them wonderfully.
Stay safe out there!