It's called an Iphone4. A charge lasts a good long time if you keep the radios (phone, bluetooth, wi-fi) turned off, and if you can understand a normal conversation, you can hear the alarm. Compass? check, altimeter? check, GPS with maps? check, stopwatch, check, Weather forecast? only if you're in range of a cell tower. Music? check, books? check, all the AT elevation profiles? check. Expensive? check.
At 1.6 oz. the High Gear ATF8 is much lighter than my solar powered Casio (approx. 4 oz) which has all the same functions including the alarm that only a dog can hear so that's a plus.
But bottom line, despite the weight and cost, if further testing shows my Iphone4 will go more than a week between charges (with judicious use)that's what I'll be taking from now on because it does so many things so very, very well.