This Other space is usually occupied by various caches and sometimes extra music backups that iTunes doesn't delete. The easiest way to do this is to simply restore and Sync your content back on.
If you don't have a jailbroken device:
- Open iTunes and plug in your device.
- Wait until iTunes shows your device.
- Click on the Sync button in the bottom right corner, don't cancel the backup.
- Now click on the Restore button in the middle of your screen. Let iTunes do its thing.
- Once it's done, iTunes will ask you to setup your device as a new device or from a backup, choose to setup as a new device. If you choose to setup from a backup, the Other space will come back
- Once it's done loading, click the Sync button to send all your music, videos, and apps back to your device.
Here's a simple tutorial that will easily free up at least 120 MB of space. This requires your iPod to be jailbroken and for you to have basic SSH skills.
The first method can be done any time after jailbreaking but the second method MUST be performed right after jailbreaking. Jump to Second Method.
1. Using an SSH client, navigate to /private/var/stash/Wallpaper.xxxxxx.
This the wallpaper that comes pre-installed on your iPod for you to use. You can delete all files in here UNLESS you got the wallpaper that you use for your locksceen from Settings, General, Wallpaper.
2. Navigate to /private/var/ stash/Themes.xxxxxx. Also, go to Winterboard on your iDevice.
In WinSCP you can delete all the file names that don't have check marks in Winterboard. It's a little confusing so click on the image to enlarge it and look at the red writing.
3. Navigate to /private/var/mobile/Library/SBSettings/Toggles.
This step is only if you have SBSettings installed and only for iPod Touch users. iPhone users, please do not attempt this. Since iPod Touch doesn't have 3G, Bluetooth, EDGE, or Phone, you can delete these files.
This makes SBSettings faster to load and respond.
4. Navigate to /private/var/mobile/Library/SBSettings/Themes.
These are the themes that come pre-installed with SBSettings. You can delete all that you are not using. If you don't know which theme you are using, you are probably using the Default theme. You can delete all the others.
This also makes SBSettings much faster to load and respond.
5. This one doesn't require any SSH skills, just some tapping required on your iDevice.
Go to Settings and then Safari. Tap on Clear History, Clear Cookies, Clear Cache.
Next time you sync with iTunes you'll notice the changes immediately. And you'll have freed enough space for a few more apps.
The above method frees up only about 20 MB, the next method will free from 75-125 MB. The method below is also required if you have just recently jailbroken.
1. Open Cydia and go to Search
2. Type in BossTool. Download and Install it
3. Press the home button and open BossTool.
4. Tap on Move Fonts. Wait until the numbers under Disk Space change, it may seem to you that it has frozen but it takes awhile.
5. Repeat number 4 with ringtones, and apps.
6. If you look at the numbers under Disk Space, you can see that you have freed up lots of space!
7. You can now go back into Cydia and uninstall BossTool.