Carry your favourite Clear Sky Charts (CSC) in your pocket! Amateur astronomers in North America monitor local sky conditions using the CSC web sites which provide a very detailed 48 hour color coded observing forecast chart for cloud cover, transparency, seeing and other factors. This app contains a database of more than 4170 forecast locations in Canada, the USA and Mexico and can check for new updates. The summary screen monitors your three favourite observing locations. Each square represents one hour and the colors vary from dark blue (excellent) to white (very poor) conditions for observing. A red line indicates local midnight and there is a last updated timestamp. Tapping on any preview chart will open a menu of options that allows you to (i) see a more detailed chart, (ii) map the chart location, (iii) open the CSC web page or (iv) select a different chart location to monitor. Locations Services can help you find nearby CSC locations when you travel. Refer to Attilla Dankos excellent CSC web site home page http://cleardarksky.com/csk for complete details on interpreting the preview and detailed charts.