I came across the Living Earth app a few days ago while looking for a decent app for using as an alarm clock. There are no shortage of these kinds of apps available but this has to be the nicest of the bunch. Beyond being a great alarm, the app is also great for weather forecasts and for displaying the current time and weather.
In the classroom:
Want an app to teach time zones, weather around the world, or even electricity use? Living Earth is a beautiful way to do so. I love how you can view the day and night views of the world and see which parts of the world are lit up. Students can really make some interesting observations from this alone.