The British phone company says, in its US-filed lawsuit, that Google has infringed on these patents in the Android operating system, apps on the Android Market, Google Maps, Docs, Music and Offers, various location-based services and most of its advertising empire.

An example patent is “Service provision system for communications networks,” which BT was awarded in the 1990s. It essentially boils down to an app figuring out whether a phone is connected to the web via Wi-Fi or 3G, and choosing to stream at a different bandwidth. Google infringes this in Google Music and the Android Market, BT ...