Tips & Tutorials

Update AT&T Galaxy S2 I777 to CM9 Final ICS Android 4.0.4 Custom Firmware

CM9 is now available for the Samsung AT&T Galaxy S2 SGH-I777. CM10 still has a lot of time before it gets officially released, but for now we will have to enjoy CM9. You can now install CM9 Android 4.0.4 ICS on Galaxy S2 SGH-I777.

In this tutorial, we will tell you how to install CM9 Android 4.0.4 ICS on Galaxy S2 SGH-I777 with complete steps using ClockworkMod recovery. Make sure you backup all the data as we will have to wipe your previous personal data and apps. Let’s begin with the tutorial below.

Disclaimer: All the tools, mods or ROMs mentioned below belong to their respective owners/developers. We ( or the developers are not to be held responsible if you damage or brick your device. We don’t have you on gun point to try out this tutorial 😉

Make sure you have installed all your USB drivers for the AT&T Galaxy S2 to connect it with the computer. Download AT&T Galaxy S2 USB drivers! Apart from just the USB drivers, there are a few more things that you need to take care of.

1. You need to enable USB debugging mode. This helps to connect your Android phone with the PC. See here: How to Enable USB Debugging.

2. Your phone battery should be 80-85% charged. If your phone goes off suddenly because of battery, during flashing ROMs or installing mods and updates — your phone might go dead permanently. See here: How to Check Battery Percentage.

3. Backup all your important data that you might need as soon as your flash a new ROM, or make a backup for just in case, you never know when anything might go wrong. See below on how to backup data:

Data can also be backed up using Samsung KIES for their devices, but if you backup data manually, you get more options what top choose from and it is very easy to move data across Android devices from different manufacturers, i.e moving Samsung Galaxy Note backup data to HTC One X.

4. Your phone should be factory unlocked. Additional instructions for locked Android devices will be added in the tutorial for unlocking devices.

Now, let’s proceed with the tutorial on the next page and update Galaxy S2 SGH-I777 to CM9 Android 4.0.4 ICS custom firmware.