Recs.
Updated
Specs
Pros
Pro Dead simple
Timer App: Select from several preset timers, or set a custom amount of time before the timer goes off.
Alarm App: Click Add alarm, pick a time you want the alarm to go off and you're done. Optionally you can go back into the alarm if you want it to persist, give it a name (provided an iPhone is connected), or if you want to disable the snooze function or to delete the alarm. From the main screen all you can do is toggle alarms on or off.
Cons
Con Must charge daily
With the Phone on Airplane Mode the Apple Watch will easily last all day leaving plenty of buffer room to charge, but still, it will require recharging on a daily basis. For many, the most convenient time to do this is as part of their bedtime or wake-up routine. Sometimes both if the watch is used as a wake-up alarm or sleep tracker.