App lets you take the planet's pulse The "Earth Now" app puts the whole world in your hands. NASA's "Earth Now" app for the iPhone lets you check the planet's vital signs from the palm of your hand. The app features a spinnable, zoomable, smartphone-sized model of Earth that takes on different types of color coding, depending on which climate data set you're wanting to see. The data sets, drawn from NASA satellite observations, document surface air temperature; show you levels of carbon dioxide, carbon monoxide, ozone and water vapor; and indicate variations in the global gravity field and sea levels. "Earth Now is a great resource for students, teachers and anyone interested in Earth's changing climate," Michael Greene, manager for public engagement formulation and strategic alliances at NASA's Jet Propulsion Laboratory, said today in a news release. Since its debut last month, it's already been downloaded nearly 170,000 times. Plans are in place for development of an Android version and for the addition of new NASA Earth science data sets over time. Earth Now is closely integrated with NASA's Global Climate Change portal page. You can download the iPhone / iPad / iPod Touch app via iTunes, or get the full rundown of programs listed on JPL's mobile app portal, including programs that serve up pictures, video and data from Saturn, Mars, the moon and other NASA missions. Take a look at these other app reports as well: