[Samsung Galaxy Nexus] Geniusdog254:
Wow. It's been a long time since I made anything useful. Not being able to use NFC with the screen off has always been a pet peeve of mine with my Nexus, so I figured I'd fix it ;)

This is a modified Nfc.apk, which is the system NFC service that runs at boot. It allows you to scan NFC tags either with the screen totally off, or with the screen on but still at the lockscreen. You get to choose which one you want to flash. Just download one of the zips below, and flash it via recovery (tested with ClockworkMod). To restore to stock, just pick the stock version.

The screen off version means you can ALWAYS scan an NFC tag. Don't have to turn the screen on or anything. Just touch the phone to the tag.

The lockscreen version lets you scan a tag whenever the screen is on, but it doesn't have to be unlocked. You can't scan while the screen is off, but you can just touch the power button to get to the lockscreen and then scan. If you have a passcode, no need to unlock your phone to scan a tag.

This has been compiled against CyanogenMod and tested on my own self-built tree based off CyanogenMod source. There is nothing here that should be specific to that ROM.

Devices

Sprint Galaxy Nexus (toroplus)

Fully working on CyanogenMod based ROMs

Fully functional on most AOKP ROMs. Throws random errors on some, but everything still works.

Not functional on some stock ROMs

GSM Galaxy Nexus (maguro)

Fully working on CyanogenMod based ROMs

Fully functional on most AOKP ROMs. Throws random errors on some, but everything still works.

Not functional on some stock ROMs

Verizon Galaxy Nexus (toro)

Untested as far as I know. If you test it let me know

Should be similar to other Galaxy Nexus SKUs

HTC One X

The user StephanSch has created a version for the One X. Get it in this post.

Only screen off seems to work, not lockscreen.

Don't know if this is for the Qualcomm S4 based One X or the Tegra 3 base. Not sure about carrier versions either.

Samsung Galaxy SIII

The user mayhemer has created a version for the SIII. Get it in this post.

I'm not aware of which version of the SIII this is for, now which ROM. As soon as I have info, I'll update it here.

Nexus S

Reported working from at least one user. Don't know GSM or CDMA version, nor which ROM.

Probably working on any CM9 build for either SKU, and possibly stock or AOKP.

It probably will not work on any manufacturer based skins on any other device.

If you try it on any other device, please let me know how it goes! I'll update the OP with your results!

Also of note, I do not know if this will allow you to use Wallet any differently than you can right now. I don't have any way to test it, and don't personally use Wallet. If you do, let me know whether it works or not so I can update this post!

Liability Disclaimer: As always, I hereby absolve myself of responsibility for any damage you cause to your phone by flashing this. There is inherent risk in modding your device, and by flashing anything in this thread you are taking that risk into your own hands. If something goes wrong, I will try and help, but I am not God.

Source Code Disclaimer: The only code modified here was given under the Apache v2 license. That means that I am not required to release source for this. It is an incredibly simple mod at this point, but I plan on taking it into the next level and creating a patch that makes this an option in settings, rather than a zip you have to flash. I will release source with this, but I want to wait until I clean it up and submit it to the CyanogenMod Gerrit as a full feature, rather than a cheap hack! Sorry if that disappoints anyone, I just wanted to get this out ASAP.

In the meantime, I explain what I'm doing in this post. That should be enough info if you're compiling from source, and might be enough if you are using a Smali edit. If you're critically concerned about it, shoot me a PM or an email and I'll try and help more.

How things stand for Jellybean:

I put this on hold for a while. The further I got into making this a toggleable option in settings, the deeper things ran into the system code. With the big change to Jellybean around the corner, I want to wait until Jellybean becomes the main CM branch so I can avoid the breaks that all the code churn will cause. I'm not done with this, but there's no point in putting the work in to make it fully functional when CM10 is around the corner to break it all. I'll get on it as soon as CM10 becomes closer to release. Before the code freeze for CM10.

In the mean time, @PHtQuE got ahold of me on Twitter and I told him what was happening. I gave him a couple pointers and he got it compiling on Jellybean at the same level it is right now on ICS. I may be wrong, but I believe this is his post right here. Regardless, this is a working screenoff version for JB.