General aviation pilots need different types of flight information in order to follow events and the changes related to the aircraft environment while flying. However, general aviation cockpits have some limitations as space to install flight displays to provide flight information beyond the basics to the pilot. Additionally, more sophisticated instrumentation is often expensive to install and maintain. With the development of the tablet-based software applications (such as ForeFlight, WingX Pro7 or Garmin Pilot applications for iPad), general aviation pilots have started to use them instead of paper documentation. These software applications provide essential flight information such as weather forecast, aviation charts, flight documents, etc. Unfortunately, the expectations for their capabilities are changing with the increased demand and popularity of these software applications. Therefore, these flight planning software applications are compared to find what is missing and what have not met the expectation of pilots. First, how the software applications support their decision-making process was described and demonstrated to choose the appropriate flight parameters to change flight path while handling with the other cockpit responsibilities. Finally, these design requirements were validated via HITL tests in a part-task flight simulator. The results provided that the suggested design requirements are found highly useful for both novice and expert general aviation pilots. Specifically, novice general aviation pilots might be able to get visualization to compare real-time weather and weather forecast, and then they might gain experience to improve their success for a in-flight re-planning. On the other side, expert pilots might prefer to use this system if they fly an airspace which they are not familiar to weather features of that region.