The Basics
Upon launching Starwalk for the iPhone, you will be presented with the all too familiar dialog asking for permission to use your location. Select yes to allow Starwalk to determine your location and display more accurate information.
Starwalk operates using the standard touch interface. Drag your finger to the left and the right to see a virtual 3D representation of the sky around you. As you pass over the constellations you will notice they become highlighted. Tap a particular point in the sky or a star to select it. A green crosshair will appear over the selected point.

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More Information
Tap the icon in the upper-left corner of the screen which looks like an "i" inside a circle. Tapping this icon will bring up more information regarding the selected target as well as a zoomed-in image. Information will be on the left hand side and includes important details such as name, visual magnitude and RA. When more information is available on the particular target a "w" inside a circle will be visible at the bottom of the information dialog. Tapping the web information icon will launch the Safari web browser and display additional information.

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Time & Date
Tap the clock in the upper right corner to change the time. Changing the displayed time will change the star map accordingly and provide accurate information about the star and constellation position at that particular time on the selected date. Slide your finger downward to activate the automatic time-forward affect which will quickly display the time changes in succession. Tap a specific hour to stop the automatic change effect. The current time and date being displayed will appear in the upper middle of the screen on the status bar.
Search Functionality
Choose the magnifying glass in the bottom left corner of the screen to initiate a search. Once selected, a search window will present itself with a list of stars and constellations in alphabetical order. Scroll through the list and tap a specific constellation or star to select it. Otherwise begin typing a name in the search bar to initiate a search. Results will be displayed below the search bar. Tap a particular result to display it on the star map. Once displayed on the star map, the result will be automatically highlighted. Tap the information icon to display information. Searches can be conducted by "Stars", "Constellations", "Solar System" or "Messier". Tap the correct choice to display a list and search for that option.