App

Kate Stewart had a torch app on her mobile phone. (AUDIO: Invocation)

Other apps included Instagram (AUDIO: The Conspiracy, TV: For Tonight We Might Die) and Candy Crush, which the Twelfth Doctor considered to be annoying. (PROSE: The Blood Cell)

In 2011, a new app on DI Ralph Finch's iPhone allowed for thermal imaging, enabling him to find Gwen Cooper's father, Geraint Cooper in their basement. (TV: The Gathering)

Dawn Shale met Duncan B. on a dating app, and the two hooked up. In the end, both were infected by an alien sexual parasite, resulting in Dawn's death. (AUDIO: Love Rat) Tyler Steele was a frequent user of such apps, (AUDIO: Changes Everything) though in time his use declined. Tyler was mortified to find Norton Folgate was using these apps to hook up with strangers while inhabiting Tyler's own body. (AUDIO: Another Man's Shoes)

In 2020, Tania Bell introduced Helen Sinclair to a mobile app involving pigs. Helen was confused about one group of characters' quarrel with the pigs, and Tania explained the game did not present much backstory. (AUDIO: Wild Animals)
 * This clearly alludes to the mobile game, in which cartoon birds are launched at pigs on various structures.

Verger had a dating app, Rabbit Chat & Date, on his mobile phone. (PROSE: Iris Wildthyme and the Unholy Ghost)

Oblation involved an app with which people could tag the homeless. (AUDIO: Hostile Environment)

The Twelfth Doctor speculated that a colony planet equipped with Emojibots might have an app used in place of going to the toilet. (TV: Smile)

The Doctor sometimes referred to their sonic screwdriver's software and settings as "apps" for various situations. (TV: Closing Time, Can You Hear Me?)

Dan Lewis had an app on his mobile phone for identifying the constellations in the night sky. (TV: Legend of the Sea Devils)