Google Maps

Google Maps launched in 2005 and has become the world's most used mapping service, covering more than 250 countries with driving, transit, cycling and walking navigation. Street View, satellite imagery and indoor maps have made it the default way much of humanity looks at the world.

Its real-time traffic predictions — derived from the movement of millions of Android phones — and a vast database of businesses, reviews and photos make it as much a local-search engine as a map. Live ETAs, popular-times charts and integrated booking deepen the lock-in.

The flip side is that location is among the most sensitive data there is. Maps' usefulness is built on continuous location collection, and Google has paid multi-state settlements in the US over misleading location-tracking controls. Users seeking an alternative usually accept fewer conveniences in exchange for maps that do not feed an advertising profile.