You might have been struck with some great features of Android Oreo, Some visual changes, some under the hood optimizations, and one such change is the Rootless theming on this iteration of Android which helps in giving a great choice of personalizing the device.
About SubstratumSubstratum is a theme engine which is widely known among Custom Roms for its working with OMS (Overlay Manager Service) functionality. These have been used after the CM Theme engine went off. Substratum doesn't overlap the overlays on individual elements. It compiles the overlays on the go, signs them and installs them. It needs no system reboots to be applied. They not only theme your system apps, they also have support or the most famous apps on Play Store. With Android Oreo, you can fully theme your device with Substratum without rooting too. For this, there are some basic needs, including a PC and a substratum theme. Click Here for more in detail for Substratum.
Diclamer: We will not be responsible if you end up bricking your device, bootlooping it or permanently damaging it. In case of Compiling Error, follow links below and Provide Subs Support proper logs.
Steps to Open Subs World
1. Install the Andromeda App and Open it, the Following screen appears
2. Extract the Given Script in PC and Run start_andromeda.bat
3. If everything is right, you can start using the Substratum
4. In Substratum app, Tap on the theme, In my case Swift Black. To enable all themes, toggle all overlays or select the ones to enable. Also, check the options under each of them to set as per your use.
5. Tap on the floating Paint roller button, tap on 'Build & Enable' and it should start compiling themes and later System UI is restarted and you get your Phone themed
What do I do, when Andromeda Update is available?
Reboot your Phone, Follow Step 1 to 3.
How to Uninstall Themes and reset to default
To Uninstall Themes, Tap on the Recovery (in Bottom Bar) - Restore theme - Uninstall all installed Overlays
Can I change Boot Animations and Fonts Systemwide?
No, It isn't supported as of now.
Where can I find more themes for Substratum?
Search for Substratum in Play store or join the Substratum Dev on Google+ to get more
1.This is a one time process unless you reboot because the app loses its connection with substratum unless rebooted, Everything's fine.
2. Even if you reboot, the Overlays you have enabled 'Won't be disabled, all will remain intact ' So no need to worry.
Credits & Sources
Nicholas for his support, R0user for the help, TechNova, XDA and the Subs Team
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