AT&T Infuse 4G SGH-I997 owners have XDA Developers member Yuma75 to thank for bringing the unofficial Android 4.1.1 Jelly Bean to their phones via the unofficial AOKP Jelly Bean-based custom ROM called CypherROM, not only giving you delicious Android 4.1.1 Jelly Bean but also unique features. What kind of features, you ask? Why don't you buckle down and flash the CypherROM to your AT&T Infuse 4G yourself to find out?

Known issues in this ROM are similar to Ice Cream Sandwich and Jelly Bean ROMs. Video recording is also choppy at 720p resolution in high light, so the developer suggests you use 480p. The Torch app is also not working but you can use third-party apps to fix that. NANDroid Backup is broken but can be fixed by flashing a packaged provided by the dev. There is also something wrong with the OC/UV settings but the developer will be fixing that in the next update.

This guide shows you how to flash Jelly Bean-based CypherROM for the Infuse 4G I997.

Warning

• The instructions in this guide are intended for use with the AT&T Infuse 4G, model number SGH-I997. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
• Read and understand the whole guide first before actually performing the instructions.

Requirements

• At&T Infuse 4G SGH-I997, with ClockworkMod Recovery installed and running an ICS-based ROM or another Jelly Bean-based ROM.  See these guides for pointers:
  • How to upgrade the Infuse 4G I997 to stock Jelly Bean build JRO03E
  • How to upgrade the Samsung Infuse 4G I997 to Android 4.1.1 Jelly Bean via CyanogenMod 10
  • How to upgrade the Infuse 4G I997 to Android 4.0.4 ICS via Infinitum custom ROM
• Download the following files:
  • CypherROM (CYPHER_ROM(calfixed).zip, 159 MB)
    • Mirror 1
    • Mirror 2
  • CypherROM Google Apps
    • Mirror 1
    • Mirror 2
• Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
  • For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

Upgrading from an ICS ROM

Follow these instructions if your phone currently runs an ICS-based ROM.

1. Download the CypherROM and CypherROM Google Apps files to your Infuse 4G's internal SD card.
2. Turn off your Infuse 4G.
3. Remove your phone's external microSD card.
4. Boot into Recovery Mode. You can do this by pressing and holding down the Volume Up, Volume Down, and Power buttons. Release the Power button when you see the Samsung logo but continue holding down the Volume Up and Volume Down keys.
5. Select Mounts and Storage and select Format /system.
6. Select Wipe data/factory reset. Confirm the action on the next screen.
7. Select Wipe cache partition and confirm the action on the next screen.
8. Go to the main menu and select Advanced. From there, select Wipe Dalvik cache and confirm the action on the next screen.
9. Select Install ZIP from SD card. Select Choose ZIP from SD card and select the CypherROM.
10. The Infuse 4G will reboot twice and then return to Recovery Mode.
11. Repeat step 9, but this time, select the CypherROM Google Apps package.
12. Select Go back.
13. Select Reboot system now.

Installing from a Jelly Bean ROM

Follow these instructions if your phone currently runs a Jelly Bean-based ROM.

1. Copy CypherROM and CypherROM Google Apps files to your Infuse 4G's internal SD card.
2. Turn off your Infuse 4G.
3. Remove your external microSD card.
4. Boot into Recovery Mode. You can do this by pressing and holding down the Volume Up, Volume Down, and Power buttons. Release the Power button when you see the Samsung logo but continue holding down the Volume Up and Volume Down keys.
5. Select Wipe data/factory reset. Confirm the action on the next screen.
6. Select Wipe cache partition and confirm the action on the next screen.
7. Go to the main menu and select Advanced. From there, select Wipe Dalvik cache and confirm the action on the next screen.
8. Select Install ZIP from SD card. Select Choose ZIP from SD card and select the CypherROM.
9. Repeat step 9 but this time, select the CypherROM Google Apps package.
10. Select Go back.
11. Select Reboot system now.

Fantastic! Your AT&T Infuse 4G SGH-I997 is now running CypherROM. Yuma75 has already promised users that he'll be working towards making CypherROM even more unique by adding additional apps, theming, and enhancements.