This app is for VFR Private Pilots, it helps you locate an appropriate Air Traffic Control Facility and Frequency. It will also display the information you need to provide to ATC for the initial contact. It uses your phone's GPS to provide proper location information for Air Traffic Controllers to pin point you on their Radar. You can now toggle between the most 10 probable ATC facilities and frequencies that can offer you flight following. You do this by Swiping to the Left/Right on the display. BTW, The application and Data is for the US Only. Also note on some phones e.g. Samsung S6 Edge, the menu icon does not appear (three dots), if you encounter that, press and hold your finger on the back button for about a second, the menu will appear. Also make sure that you give this application "Location" permission otherwise nothing will work, as it uses your location to work properly.

If the App start properly check: To allow this app Location Permission, without it it won't work. Go into settings and allow permissions for this app