One UI is a user interface (UI) developed by Samsung Electronics for its Android devices running Android 9 "Pie" and later. Succeeding Samsung Experience and TouchWiz, it is designed to make using larger smartphones easier and be more visually appealing. To provide more clarity, some elements of the UI are tweaked to match colors that are based on the color of the user's phone. It was announced at Samsung Developer Conference in 2018, and was unveiled in Galaxy Unpacked in February 2019 alongside the Galaxy S10 series, Galaxy Buds and the Galaxy Fold.

Android is a mobile operating system based on a modified version of the Linux kernel and other open-source software, designed primarily for touchscreen mobile devices such as smartphones and tablets. Android is developed by a consortium of developers known as the Open Handset Alliance, though its most widely used version is primarily developed by Google. It was unveiled in November 2007, with the first commercial Android device, the HTC Dream, being launched in September 2008.