Downloading QGroundControl 4.2.8 from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this software available. The following versions: 4.0, 3.2 and 2.9 are the most frequently downloaded ones by the program users.
The program's installer file is commonly found as qgroundcontrol.exe. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. This free program is an intellectual property of QGroundControl. This PC program is suitable for 32-bit versions of Windows XP/Vista/7/8/10/11. QGroundControl lies within Development Tools, more precisely IDE.
From the developer:
QGroundControl provides full flight control and mission planning for any MAVLink enabled drone. It provides configuration for ArduPilot or PX4 Pro powered vehicles. Its primary goal is ease of use for first time and professional users. All the code is open-source source, so you can contribute and evolve it as you want.
You may want to check out more software, such as FlashDevelop, Raize Components or LispWorks, which might be related to QGroundControl.
Travel