[Verizon Samsung Galaxy S 4] joderme:
Update (7/11/14):

Updated for the July 2014 version of ISIS - New mod is 3.1

Also if this has worked for you please at least hit the thanks button!

Update (4/9/14):

There are various versions below as you can see. Version 1 is meant to work with ISIS versions 1.9 and below. Version 2 works with ISIS installed before 4/9/14 (ISIS 2.0). Version 3 works with ISIS installed on or after 4/9/14 (ISIS 2.01.00-build.15.30+)

Also if this has worked for you please at least hit the thanks button!

Description:

This method will help you get ISIS wallet running on your rooted Galaxy S4 as ISIS performs a root check and will not work if your phone is rooted. An alternate method is that you can hide root, busybox, etc, however, is personally less desirable for me. This will work on other devices on other carriers as well assuming you have an ISIS sim.

While I know many folks won't use ISIS or will bash it, some can't get GW installed on their device (especially on ME7) and this is the only option for them. Additionally, without widespread carrier support who knows if and when GW will be mothballed.

As always proceed at your own risk as I am not responsible for a borked phone. If you have a custom recovery always do a nandroid backup.

Note: You must have an ISIS sim card and be rooted to use this method and there are different requirements if you are using a custom ROM.

Note: If you have used the Google Wallet workaround then this should still work, however, GW will compete to complete the transaction so it must be frozen before using ISIS

Methods:

Stock TouchWiz:

Ensure phone is rooted and ISIS sim card installed

Install ISIS and verify that you are receiving the "phone is rooted, cannot start" message.

Install the Xposed framework app - http://xdaforums.com/showthread.php?t=1574401 (read over the thread to ensure compatibility)

Open the Xposed app and click "Install/Update," it should ask for root - grant it and install

Reboot the device

Install the Xposed ISIS Root Bypass module apk - See below for links to various versions.

Launch Xposed Installer app and go to the "Modules" tab

Activate ISIS Xposed module by checking the checkbox next to it

Reboot

Open ISIS and spend away!

Other ROMs/Devices:

Ensure the necessary files are installed for ISIS/NFC functionality - some ROMs do not include all of these files or variations of them.

Other devices and some ROMs may have issues with the build.prop - you will know this if you can't see ISIS in the market or get in app errors.

Once this is done proceed with the steps listed above in the Stock TouchWiz section

Necessary files (if not on stock TouchWiz):

/system/app/NfcTest.apk (and odex if not deodexed)
/system/app/NfcNci.apk (and odex if not deodexed)
/system/app/SmartcardService.apk (and odex if not deodexed)
/system/framework/org.simalliance.openmobileapi.jar (and odex if not deodexed)
/system/lib/libnfc-nci.so
/system/lib/libnfc_nci_jni.so
/system/lib/hw/nfc_nci.MSM8960.so
/system/etc/nfcee_access.xml - ensure the contents contain an ISIS signature such as below:

[CODE]<!-- VZW ISIS PROD Signature -->
<signer android:signature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
</resources>

[/CODE]

Credits:

[MENTION=711482]beaups[/MENTION]: providing the areas to subvert for root checks and necessary files.

[MENTION=4419114]rovo89[/MENTION] for the Xposed module

[MENTION=429709]itsmikeyj[/MENTION] and [MENTION=4111823]rayjr13[/MENTION] for helping to test and troubleshoot issues