Industry standards for building high-performance mobile and web apps.
These are modern IDEs that have replaced Flash Builder for most development tasks.
If you are looking to build cross-platform applications today, most developers have transitioned to more modern, secure, and actively supported frameworks: About Adobe Flash Builder 4
Downloading software from torrent sites or sources claiming to provide "serial keys" for paid products carries significant security risks:
Originally released as a tool for building mobile and desktop applications using ActionScript and the open-source : About Adobe Flash Builder 4
Using pirated software violates copyright laws and terms of service. About Adobe Flash Builder 4.7
For developers still maintaining legacy Flex applications, the software can sometimes be run by updating it with the latest AIR SDK from Harman , who took over support for the AIR platform. Modern Alternatives About Adobe Flash Builder 4
Popular open-source alternatives that allow developers to use ActionScript-like code to target multiple platforms (web, mobile, desktop).