Android One — launched by Google CEO Sundar Pichai — is a line of Android devices targeted at first-time smartphone users in emerging markets and, increasingly, in Europe and North America. Android One devices are stock Android phones, and Google designs, develops, and markets new devices, while OEMs handle all the manufacturing.
Essentially, the goal is for Android One to facilitate the spread of Google-controlled Android among the next billion (or two billion, or more) smartphone buyers by offering a compelling entry-level product, aided by local OEMs. In turn, the fact that manufacturers won't need to worry about software or sourcing hardware components means they can turn around products more quickly. From Google's perspective, Android One lets the maintain more control than is possible in the wild west that is the general Android ecosystem, and ensure that Google services and Google's design language are front and center.
In 2014, Android One phones were first released in India, Nepal, Bangladesh, Indonesia, the Philippines, Sri Lanka and other South Asian countries. Some of the initial Android One devices include the Mircomax Canvas A1, Spice Dream UNO, Karbonn Sparkle V, Mito Impact, Nexian Journey One, and Cherry Mobile One.
Since then, phones have launched in Turkey, parts of Europe and the U.S. from companies like Motorola and HTC.