I had none of the problems mentioned by others

I have an iPhone 6plus and have always used the standard alarm. This is much better. I never experienced any random failure to work and as someone else mentioned, most alarms will not go off if your phone is in the DND mode. My only complaint would be having to reset it every day. Wish there was a way to set it once and have it go off on specified days (ie Mon-Friday)

cmathew about Alarm Clock - ZenAwake