Every manufacturer seems to be working harder than ever to bring the latest version of the Android operating system called Marshmallow to their own devices as fast as they can. Still, there are not many devices out there running this new version, but, since Google released the software a while ago, a few developers have been working with it so they can port it to more devices unofficially. The fact that anyone can modify many aspects of the OS is one of its most important advantages and developers have created many custom ROMs that allow further customization for users. While Android has been optimized over time to use fewer resources, it's sometimes fun to see new software running on older devices just for the sake of it, plus it's always nostalgic to see their outdated designs get new life.
The Samsung Galaxy S was a big deal when it was released back in June 2010, not only because it established "Galaxy" brand for the company, but it also helped Android to become more popular. Now, XDA user sooti got Android Marshmallow running on the Galaxy S through OmniROM. He even explains how to install this new software on this device for those advanced users, although he makes it very clear that installing it is responsibility of the user. He also mentions that this software is in the Alpha stage, so it will be unstable and some features will become unusable. What works in this version include the radio interface layer (RIL), WiFi, Bluetooth, sensors, the camera can be used with third-party apps, internal SD, audio and vibration motor, the buttons (although pressing the home button to unlock doesn't work yet) and the USB storage.
The components that are not currently working include the GPS sensor and SELinux among other smaller features. Some of the issues and bugs seem to be caused because the procedure wasn't done exactly as indicated. The software only works on the I9000 model and the developer seems committed to optimizing it so it can become more usable. Still, it's quite an achievement to install current software on a device that is more than 5 years old.