Tango, or Project Tango, was an AR (Augmented Reality) computing platform Google released in 2014. It allowed mobile devices to calculate their position relative to the surrounding environment using just the device’s hardware and software and without the help of GPS.
App developers utilized this to offer users features such as 3D mapping, physical space measurements, indoor mapping, etc.
The decision was somewhat unexpected since Google had been promoting the technology earlier in 2017. However, it seems Apple’s announcements about their ARKit platform on iOS11 forced Google to re-evaluate their AR strategy.
In truth, Tango never turned into a mainstream platform. It required specialized hardware available on a limited number of devices, such as Pixel, Pixel 2, and Asus ZenFone AR. On the other hand, ARCore simplified things using plane detection and not building a 3D mesh of space.
Google claimed these changes would allow ARCore to be compatible with up to 100 million devices by the end of 2018, including most Android phones released that year.