CyanogenMod is based on the Android Open Source Project with extra contributions from many people within the Android community. It can be used without any need to have any Google application installed. Linked below is a package that has come from another Android project that restore the Google parts. CyanogenMod does still include various hardware-specific code, which is also slowly being open-sourced anyway.

What's working:

• Wifi (connection, tethering, etc)
• Bluetooth
• Camera, video codecs
• RIL (Calls, SMS, mobile data)
• Storage (both internal and external)
• MTP storage (both internal and external)
• Offline charging
• zRAM (compressed-RAM swap)
• GAPPS
• Tethering (USB, Wifi, Bluetooth)
• GPS
• Sound recording
• Torch (flashlight)

BUGS/Not working :

• There're lots of bugs, but main are
• Switching to other fonts will get bootloops after restart. In this case, if you use TWRP recovery, go to File Manager >> delete "themes" from /data/system would help you escape this without factory reset
• Distorted Bluetooth sound on calls

First time installing CyanogenMod 12.1 to your Galaxy V, or coming from another ROM:

• Install TWRP Recovery
• Reboot into Recovery using 3-button-combo (Vol-up+Home+Power)
• Do a Nandroid backup! (Optional and only if you weren't running TouchWiz before)
• WIPE (wipe data/factory reset + wipe cache partition + format /system partition)*
• Install the ROM from sdcard using TWRP Recovery

CHANGELOG:

- ALPHA-1

Initial release

- ALPHA-2

Fixed ION driver, now camera, video codecs, etc are working

Fixed audio

Dual-SIM is dead for now

Reserved zRAM size to 128MB

- ALPHA-3

• Fully fixed RIL, will switch to beta on next builds
• Fully fixed Bluetooth

- BETA-1

• Faster app installation, but slower app startup, a trade-off!
• Improve media playback: some media app can play flawlessly, but not YouTube, sorry
• zRAM size now can be set in build.prop

- BETA-2

• Fixed audio stuffs
• Fixed video decoding stuffs (included YouTube)
• Fixed video recording
• Don't remember list start, blah blah...

- BETA-3

• Updated sources, Android security patch version 2016-04-01
• Switched memory allocator to dlmalloc(), which increase performance a lot
• Odexed apps now will be in /system partition, not in /data/dalvik-cache anymore (significantly save internal storage, as this thingy eats up to 300MB of our internal storage)
• Powered by OC Kernel (unexpectedly compiled ) 

- BETA-3 update 1

• Fixed random reboots, switched to stock kernel