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I use it as my only alarm clock. Has worked perfectly for the last 4 years for me.

Same here.

My only hiccup so far in 4 years of iPhone alarm clock usage was actually just this past Thursday. My alarm either didn't go off or I somehow turned it off without waking up or remembering it. But I still managed to wake up (thank God), randomly, on my own about twenty minutes later and made it to work on time.

However, if you believe the interwebz the iPhone is apparently "notorious" for the alarm randomly not working
 
It hasn't always been reliable for me. I still use it, but I set more than one alarm, and I also set an alarm on my iPad. Just in case.
 
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The phone's alarm clock has never let me down. Just pick an annoying alarm tone.
 
With one exception (going from UK to US on the day before the DST change), the iPhone has worked perfectly for me. Indeed, given that we suffer occasional power outages where I live, it is more reliable than a cheap alarm clock/radio because it has a battery. There have been times when I have been the only one on time to work because my colleagues' alarm clocks failed. If you want to be certain of getting up, then you can set multiple alarms...

Mind you, I also use the alarm feature of the cordless phone that sits on my nightstand as a backup alarm. It too has a battery.
 
Alarm malfunction

My alarm on my standard spec iPhone 3GS has gone AWOL. It rings when it wants to throughout the day. When it does ring it cuts off anytime it wants too, and usually does not go off on the set Time. Shame the iPad doesn't come with a bog standard alarm app. Have to resort using the blackberry alarm, annoying though it is, I definitely wake up to it. Anyone else having such crazy issues? Think I need to replace my phone now. Come on apple release iPhone 5 soon pls. Lol
 
Been using the alarm on iOS for the past 3 years. Never a problem, even with DST. But some did, and they fixed that with an update to the OS.

I have 3 separate alarms that go off every weekday, and they all work like a charm.

If you're looking for a dock, the iPhone alarm clock will work great for you. Save the cash.
 
The only thing to be wary about is when daylight savings time begins or ends.
Seems like Apple has screwed this up every year since the iPhone began.
I think this most recent daylight savings was the first one that wasn't effected by some bug or an other.

That was the only time it let me down, the rest of times works 100%
 
I don't know if its an iOS5 beta-6 thing or if I've just suddenly become a heavier sleeper but since installing beta-6 the alarm on my 3GS has let me down multiple times.
 
Not reliable for DST

I rely on the alarm daily, but it has failed my twice on daylight savings switch overs. I do NOT trust it at all anymore for those times. I understand that DST is a screwy thing, and that timezone management is also rather complicated, but it is ridiculous that Apple keeps stumbling on this.
 
My alarm on my standard spec iPhone 3GS has gone AWOL. It rings when it wants to throughout the day. When it does ring it cuts off anytime it wants too, and usually does not go off on the set Time. Shame the iPad doesn't come with a bog standard alarm app. Have to resort using the blackberry alarm, annoying though it is, I definitely wake up to it. Anyone else having such crazy issues? Think I need to replace my phone now. Come on apple release iPhone 5 soon pls. Lol

I haven't had the same issues as you but my alarm would not sound last week. The popup would show but no noise. I fixed it by resetting settings (General>Reset>Reset All Settings). I have a 3G (3.1.3) and not a 3GS but maybe that might help fix some of your issues.

In regards to the thread topic, I have been using the iPhone alarm clock exclusively for the last three years and the only issue I have had is the one I mentioned and I only had that issue once. I would say that the alarm is pretty reliable (other than some DST isssues as others have noted).
 
Love the fact that I can set a work alarm clock for weekdays only, and I only have to set it ONCE. After it's set up, it remains so until I remove it or turn it off. I get up at the same time every single weekday and don't have to "remember" to set the alarm... it does it completely automatically :)
 
I need a dock and wondering if I should get an alarm/dock combo or just a dock... is it pretty reliable?

I trust it, just make sure you have more than 10% of battery before going to bed, also keep the background apps to the minimum, I shut them all off.

edit: oh, it's not about the phone itself, it's about the dock... my bad, wrong comment.
 
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