Chainfire's screen modifying app CF.lumen has been updated to v3.0 with a few important changes, not least of which is a mode for unrooted devices. You won't get full functionality, but it's better than nothing, right? If you want to verify that, you can also get all the pro features for free now. Seriously.
Here's the changelog for v3.0.
- Added KCAL driver (see XDA thread for details)
- Added Rootless driver (see XDA thread for details)
- Added freeload option
- Backuptool script updated (requires un-/reinstall of driver to become active)
If you load CF.lumen on an unrooted device, it will automatically default to using the rootless driver. This makes changes to the color profile of the screen by adding an overlay, which is what most apps of this sort do. The root method allows for much higher image quality, but the overlay gets the job done.
For rooted users, there's support for the KCAL driver, which works with the popular KCAL kernel mod on Qualcomm-based devices. There is no performance impact using this driver, but the image quality isn't quite as good as the original CF.lumen driver. It's still better than unrooted mode, though.
The Freeload option has shown up in a few of Chainfire's apps, and now it comes to CF.lumen. Just enable this option to get all the pro features for free. You should probably still buy the app ($2.99) if you like it. This might not be a permanent change, so don't get too comfy.