If you want to reinstall Cydia to your iPhone,iPod,iPad or iPod Touch then you don’t require to jailbreak your device again.
Cydia is being developed by Jay Freeman aka Saurik and is similar to App Store where you can download tons of apps for your idevice either for free or by paying a small sum.Installing Cydia requires a jailbroken device.
Steps to follow to reinstall Cydia without re-jailbreaking iPhone
1. Download Cydia .deb file from here.
3. After placing the .deb into the ROOT, type the following commands to reinstall Cydia-
dpkg -i /Cydia.deb
killall -HUP SpringBoard
You have now successfully reinstalled Cydia on your iPhone,iPad oriPod Touch.