Downgrade iOS 10.3 to iOS 10.2.1

Downgrade step guide

* Before start downgrade process, you should complete necessary requirements such as
* Download latest iTunes version
* You must disable Touch ID feature and passcode- Settings > Touch ID & Passcode
* Turn off find my iPhone Settings > iCloud > Find My iPhone
* Download specific IPSW file according to your Device model and save it to desktop
Download latest iTunes
* Plug device to PC
* Open iTunes and go to Summary panel and click Connected iOS Device
*Now click iTunes Restore option with following keys
Windows Left Shift Key
Mac Option + Alt
* Now select previously installed IPSW file
* Now iTunes will start Restore and once finished go through Settings and setup the Device.

Downgrade after stop sign

After Apple stop firmware sign, you cannot downgrade with the support of iTunes as a normal. Therefore, you should save SHSH blobs for the future downgrade.
SHSH blobs

How to save SHSH blobs?

For the SHSH blobs save you should use compatible software. At this time, TinyUmbrealla / iFaith and Redsn0w are the common software
TinyUmbrealla compatibility up to iOS 8.1.2
iFaith compatibility up to iOS 6.1.3

Downgrade troubleshooting

iTunes incompatible firmware error make sure to download correct firmware version according to your device model.
iTunes Error 3194 if you receive this message continuously while on downgrade you cannot complete downgrade because Apple closed signing window.
Welcome to the
Cypple Website

Downgrading is installing Apple previous iOS firmware version. Currently iOS 10.3 Beta can downgrade to iOS 10.2.1 version.
Download iOS 10.2.1 IPSW

iPad Pro iOS 10.2.1 IPSW
12.9-inch iPad Pro (WiFi)

12.9-inch iPad Pro (Cellular)

9.7-inch iPad Pro (WiFi)

9.7-inch iPad Pro (Cellular)
iPad Air 2 (6th generation WiFi)

iPad Air 2 (6th generation Cellular)

iPad Air (5th generation WiFi + Cellular)

iPad Air (5th generation WiFi)

iPad Air (5th generation CDMA)

iPad (4th generation CDMA)

iPad (4th generation GSM)

iPad (4th generation WiFi)

iPad mini 2 (WiFi + Cellular)

iPad mini 2 (WiFi)

iPad mini 2 (CDMA)

iPad mini 3 (China)

iPad mini 3 (WiFi)

iPad mini 3 (Cellular)

iPad mini 4 (WiFi)

iPad mini 4 (Cellular)
iPad iOS 10.2.1 IPSW
iPhone iOS 10.2.1 IPSW
iPhone 5 (CDMA)

iPhone 5 (GSM)

iPhone 5c (CDMA)

iPhone 5c (GSM)

iPhone 5s (CDMA)

iPhone 5s (GSM)

iPhone 6

iPhone 6 Plus

iPhone 6s

iPhone 6s Plus

iPhone 7 (iPhone9,1)

iPhone 7 Plus (iPhone9,2)

iPhone 7 (iPhone9,3)

iPhone 7 Plus (iPhone9,4)

iPhone SE
iPod touch iOS 10.2.1 IPSW file
iPod touch (6th-generation)