Deleting transferred purchases from iTunes cache I'm using a long-lived installation of MacOS X alongside with an iPhone and iPad. Because of backups of both devices and the purchased applications, I'm losing a considerable space (~14GB) in my system.

Is it safe to delete the transferred files (from finder, terminal, etc.) or is there a way to do it from iTunes.
To delete Apps from iTunes just go to the Apps section of iTunes.
Select the desired Apps(cmd+click for multiple selection) and cmd+backspace to delete the files.

Your purchases will not be gone, since you can always download them again from the iTunes Store.