How to Save SHSH2 Blobs for Unsigned iOS Downgrade / Upgrade
Here's how you can save your iPhone, iPad, iPod touch's SHSH2 blobs for downgrading or upgrading to unsigned iOS firmware later using Prometheus.
Save Your SHSH2 Blobs Now, Allowing You to Upgrade or Downgrade to Unsigned iOS Firmware on the Fly
A new tool, called Prometheus, is all set to land on New Year's Eve, allowing users to jump onto any version of iOS that is currently not being signed by Apple. While that may sound too good to be true, it's worth noting that there are certain prerequisites that you have to follow in order to kick things off.
You need to have SHSH blobs saved for the firmware you are upgrading or downgrading to. But not regular blobs will do; they should be saved in the new .SHSH2 format. In today's guide, we will show you how to save blobs for your device, allowing you to restore back to iOS 10.1.1, or any other firmware for that matter in the near future.
You can utilize tihmstar's tsschecker tool to get things done, but it might be a little too complicated for some people. Therefore, it's best to utilize an online based tool called auto-tsschecker, created by Reddit user 1Conan, that automates the entire process by a huge margin.
Find Your Device's ECID & Identifier
To kick things off, connect your iOS device to your computer via USB and launch iTunes. Once launched, select your device from the top left hand corner. Now click on the Serial Number field until you see your device's ECID. Simply right-click on it and copy it to a safe location. The ECID you saved is in decimal. But you will need to convert it to hexadecimal format. You can do so using any online tool.
The iOS device you are using has an identifier and you can find it quite easily by doing a quick search on the Web. It looks something like this for the newer iPhone 7 models: iPhone 9,1 or iPhone 9,2 and so on. If you can't find anything on the Web though, then be sure to check out this link for some help: theiphonewiki.com/wiki/Models
Save SHSH2 Blobs
Once you have followed the above steps, open the following link in your Web browser: tsssaver.1conan.com
You will be required to enter your ECID (in hexadecimal) and identifier. Once done, simply click on the Submit button. The SHSH2 blobs will be saved there and then.
Please make sure you save the resulting link in a safe place otherwise you will be left in limbo. But if you your ECID at hand, then you do have the option of keeping your blobs in tact. Just visit the link above for more details.
I will highly recommend saving your blobs right now, especially if you are a jailbreaker. If you really don't care about a jailbreak or the process of downgrading, then you may continue without worrying about anything at all.