Did you know that iTunes keeps a back-up copy of every iPod, iPhone, and iPad software update ever downloaded? If you’re a long time “iDevice” user or have multiple devices in your family synced to the same machine, these updates can really add up in terms of disk space. With the introduction of more feature robust products such as the iPod touch, iPhone, and iPad, software updates have grown considerably in size. If left unchecked, these updates can devour precious hard drive space. Since a circumstance requiring you to revert to a previous version of software would be considerably rare, these extraneous copies are safe to delete.
To clear out this collection of amassed updates, simply navigate to: Your Home Folder/Library/iTunes. Here, you’ll find folders containing updates for any devices synced with your machine. It might be a good idea to save the most recent update just in case you need to restore your device, but older updates can safely be trashed and deleted. If you’ve been steadily updating an iPod or iPhone over the past few years you’ll likely reclaim anywhere from a few hundred megabytes to one or two gigabytes. If for whatever reason you find yourself in need of an older update, all of them can be found and downloaded here