You must first have a rooted android device to do this.
Step 1. Download the Verizon custom ROM or AT&T custom ROM you want to install on your Galaxy S4 and copy to either internal or external storage on your phone. You should only install ME7-based firmwares. I highly recommend HyperDrive ROM for Verizon S4.
Step 2. Download latest version of SafeStrap from XDA:
Download SafeStrap for Verizon Galaxy S4 from XDA.
Step 3. Open and Install Safestrap APK file using My Files app.
Step 4. Open Safestrap app and choose “Install Recovery” then “Reboot to Recovery”.
Step 5. Choose “Boot Options”.
Step 6. Choose “ROM-Slot-1″. You will notice you can create up to four different ROM slots. Yes, you can have 4 different custom ROMs installed if you want.
Step 7. Choose your data partition size and choose “Create ROM slot”.
Step 8. When done, go back to main menu and choose “Wipe”.
Step 9. Swipe to do a factory reset.
Step 10. This is IMPORTANT! If you get “Unable to mount internal storage” error, you need to reboot recovery. If you don’t get that error, skip to Step 14.
Step 11. Choose “Reboot” and “System”.
Step 12. When rebooting, hit the Menu button when you see the Safestrap menu during boot. That will enter you back into Safestrap Recovery.
Step 13. Try wiping again, this time you should just get “Updating partition details”.
Step 14. Next, choose “Install” and find the ROM zip file you want to install and install it.
Step 15. When done installing ROM, reboot and you should see your new custom ROM booted! That’s it!
Anytime you want to revert back to stock ROM, it’s easy to do. Just reboot into recovery (hit Menu button during boot when you see Safestrap Recovery menu) and select Stock ROM under Boot Options.
Step 1. Download the Verizon custom ROM or AT&T custom ROM you want to install on your Galaxy S4 and copy to either internal or external storage on your phone. You should only install ME7-based firmwares. I highly recommend HyperDrive ROM for Verizon S4.
Step 2. Download latest version of SafeStrap from XDA:
Download SafeStrap for Verizon Galaxy S4 from XDA.
Step 3. Open and Install Safestrap APK file using My Files app.
Step 4. Open Safestrap app and choose “Install Recovery” then “Reboot to Recovery”.
Step 5. Choose “Boot Options”.
Step 6. Choose “ROM-Slot-1″. You will notice you can create up to four different ROM slots. Yes, you can have 4 different custom ROMs installed if you want.
Step 7. Choose your data partition size and choose “Create ROM slot”.
Step 8. When done, go back to main menu and choose “Wipe”.
Step 9. Swipe to do a factory reset.
Step 10. This is IMPORTANT! If you get “Unable to mount internal storage” error, you need to reboot recovery. If you don’t get that error, skip to Step 14.
Step 11. Choose “Reboot” and “System”.
Step 12. When rebooting, hit the Menu button when you see the Safestrap menu during boot. That will enter you back into Safestrap Recovery.
Step 13. Try wiping again, this time you should just get “Updating partition details”.
Step 14. Next, choose “Install” and find the ROM zip file you want to install and install it.
Step 15. When done installing ROM, reboot and you should see your new custom ROM booted! That’s it!
Anytime you want to revert back to stock ROM, it’s easy to do. Just reboot into recovery (hit Menu button during boot when you see Safestrap Recovery menu) and select Stock ROM under Boot Options.
