[AT&T Samsung Galaxy S II Skyrocket SGH-I727] NoSpamDan:
Changelog:

NOTE: I don't have time to maintain this list, but will try to post notable fixes and/or updates in the announcement posts for new builds.

Some of these features are added by myself and may or may not continue to show up in the builds. Slim has started the weekly builds, but don't expect those builds to have features that aren't merged yet, like some of the below ones!

Slim-skyrocket-5.1.1.alpha.0.1-UNOFFICIAL-20150510-0221.zip

MD5: ba0df799af5c2b1bec60b97929f1a82f

Fix mobile data issue(s)

Possible lag/wake from sleep improvements

Quick Settings tile customizations

Latest Slim commits...

Slim-skyrocket-5.1.1.alpha.0.1-UNOFFICIAL-20150426-2142.zip

MD5: 70f4884c4ed92879391e417de3f6b81e

Fixed Phone app FC

Display overlay CAF fixes

Mobile data may still have issues. WIP

Slim-skyrocket-5.1.1.alpha.0.1-UNOFFICIAL-20150423-1933.zip

MD5: 1526faeadc3b6545b292b8c936ff805e

Removed default DPI

Added low memory adjustment

v5.1.1 updates across the board

Slim-skyrocket-5.0.2.alpha.1.0.3-UNOFFICIAL-20150331-1044.zip

MD5: a585a75fab0458211c738d67213646b2

Torch/Flashlight tile is working

Low memory optimizations

Latest Slim WIP commits from RobbieL811

Slim-skyrocket-5.0.2.alpha.1.0.3-UNOFFICIAL-20150322-0521.zip

MD5: b2f1b55c3b6ba2bec3f1473d90d06c68

New features like Blacklist, expandable volume panel, and SlimCenter (not fully functional to inform of updates yet).

Basic BLN support in the kernel. Enable/disable it in Settings > Sound & notification > Notification > Notification light

Should be a noticeable improvement in the occasional lag, but there seems to be a general bug related to this that affects many devices. With our device, it's more noticeable due to lower resources in general than newer devices have.

Default DPI is now set to the native device default of 240, but you can change this to several preset values in Settings > Display > LCD density.

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150312-1448.zip

MD5: 2131cca37fb25c74d05653dce053318c

Updated WiFi, camera and display vendor blobs.

Wifi: removed sockets implementation.

Lagginess should be improved, if not gone...

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150305-0204.zip

MD5: cf7bba521709785eca9354829e784b72

Power-off charging is fixed, along with animated images and even % display during power-off charge. So if your phone dies, you can charge it back up without issue!

BLN (Button Light Notificaiton) support, and it can be disabled if you want in the Settings menu! (Sorry no per-app control right now.) Thanks to [MENTION=4779996]gimmeitorilltell[/MENTION]!

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150228-2118.zip

MD5: 23b09052ec18783266037088a47f7bd2

Kernel fix for keypad null pointer.

Fix for first install WiFi HAL soft reboots.

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150226-1520.zip

MD5: 7dc4acb4e25c5daff59f0b4b31f318fd

Added power menu customization

Added SlimCenter

More Quick Settings updates, including a Reboot tile

Many other updates

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150222-0036.zip

MD5: 6896fb4aed5d9c3d56093e118fc932e8

Added Slim's new hardware key rebinding

MMS updates and fixes

USB Charging

Updated Quick Settings tile customization

Show each app name being optimized during boot

Slim-skyrocket-5.0.2.alpha.1.0-UNOFFICIAL-20150221-0122.zip

MD5: f74766fd46b6bd7f3e53b349eeebeede

Soft reboots fixed!

Fix for possible NFC bug.

Quick Settings tiles customization (Settings > Interface > Quick settings). Note: there still may be bugs...

Battery icon customization (Settings > Interface > Status bar > Battery icon options)

DPI changer (Settings > Display > LCD density)

Cursory RRO Theme suport. Slim is currently not implementing CM's theme engine. RRO is better in many ways... If you don't know what RRO Themes are or how to use them, you need an app and theme apks. Check it out here: RRO Themes App Official Thread and here: some RRO themes hosted on RobbieL811's server. Thanks, [MENTION=4911350]RobbieL811[/MENTION]!

Audio policy tweaked some more - Please test various audio/video scenarios.

Ringtones may not appear until after the Media Scanner picks them up, the phone sleeps, or a reboot. Not sure which at this point, but they are there!

Various other updates and code clean-up

Slim-skyrocket-5.0.2.alpha.0.91-UNOFFICIAL-20150214-2343.zip

MD5: 5f231fbf4e38f1dc8dc1f660b18463eb

Mobile data and MMS are working now! Thanks to [MENTION=4800121]Sultanxda[/MENTION] for pointing me in the right direction!

Camera API updates and bug fixes (no 1080p yet though)

Torch

Audio policy cleaned up

Media codecs cleaned up

MTP transfer mode is selected by default

Removed unused libaudioamp config

Re-enabled qcom aac encoder

Removed call volume steps prop overrides

Removed PowerHAL

Various other updates and code clean-up

Slim-skyrocket-5.0.2.alpha.0.91-UNOFFICIAL-20150205-2203.zip

MD5: fcac1bdad6b3f1fae35fde4fe10c711e

Moved almost all code to Slim source.

Using modified CM kernel, compiled inline with the ROM using gcc 4.8 armeabi kernel toolchain

Using new msm8660 CAF branches

Device code updates and clean-up

Slim-skyrocket-5.0.2.alpha.0.91-UNOFFICIAL-20150203-1411.zip

Audio now works

Kernel booting and compiled with gcc 4.8 armeabi toolchain

New modified kernel based on CM 12.0 msm8660-common kernel

Media/codec updates

My underwear - when I first heard SlimLP audio on the Skyrocket!