Data for US customers is provided by Dynon Avionics for no fee. The following is released on the FAA standard 28 day cycle. This is the most comprehensive data available for the US, including smaller airports and AFD remarks not available in other databases. And it's free!
|SkyView 7.0 and higher||
US Aviation Database: Valid: July 20 - August 16
US Obstacle Database: Valid: June 22 - August 16