Supporting versions 2.3 through 4.2 of Android, the Substrate will allow users to use WinterBoard with supporting icon packs on stock ROMs. While this has been available for a while under Xposed Modules for Android, it’s nice to see some competition come and additional support for older versions of Android. Furthermore, Substrate doesn’t modify any system software, only acting as an add-on to your current OS. While the “theming” component is only a small part of the Substrate capability, but probably one of the most well known uses for it up front.
As noted by Saurik, the developer:
“Substrate for Android is new. While I've spent a bunch of time testing it on a bunch of devices with many versions of Android, there is always the possibility that there's something unique to your setup that causes an incompatibility. If possible, I'd recommend having a backup of your device handy; I'd also recommend being setup with a recovery mode image that allows you to easily delete Substrate”
While being new to Android, the Cydia Substrate has been on the iOS scene since 2008 and has proven to be a viable competitor against the Apple Store. The potential for Android includes many “tweaks” to the system that could help make the OS more user friendly; being able to change the behavior of the home screen, adding capabilities to stock programs, and much more. While Android is in itself an open platform, the release of the Substrate allows you to install this type of extensions without replacing them.
Check out the Substrate here in the Google Play store. Please note the overview and warnings associated with installing this type of platform on your device. Installation and use of this at your own risk.