Substratum is an incredibly popular theming system for smartphones and tablets running compatible firmware. It has evolved from Sony’s RRO framework and used to be called Layers until it evolved into the Substratum project that we know of today. We’ve talked about Substratum on multiple occasions here on XDA and have even produced a few tutorial videos so you can theme elements yourself. The process can seem tedious and there is some setup involved before you can get things to look the way you want.
However, there’s a new open source application from XDA Member Android-xp that promises to let you make your own Substratum themes all from your own smartphone or tablet. The application is called OTGSubs and you can find the open source project on GitHub or download the official application from the Play Store. Creating and packaging a Substratum theme directly from your device isn’t all that OTGSubs allows you to do, though. Themers, if they choose to, can make their existing themes compatible with OTGSubs if they want.
Thus if your favorite Substratum theme also supports OTGSubs, you can then load up that theme into the application and customize certain elements such as background and accent colors. The developer says the application is still in an alpha stage and there could be some rough edges that need to be fixed. Still, creating a basic theme is very straight forward and you can see how the process works by watching the embedded video down below.
OTGSubs (which stands for On-The-Go Substratum) currently contains three modules: app, substratum-packager, and substratum-template-patcher. The developer has even been in touch with the Substratum team and they’re working to see if this functionality can be directly implemented into the core Substratum application. Be sure to check out the application if you’re interested and tell us what you think down in the comments section below.