Outlier droid

An Outlier droid is an android used for observation of a specefic area from a far distance, taking the shape of whatever the inhabitants of said area looks like. Its eyes would occassionally flash blue, revealing its true identity.

One such android, in the form of a little girl was employed by the Shakri to monitor everything that happened during the The Year of the Slow Invasion when the Shakri, acting on orders from "the Tally", sent out cubes meant to rid the universe of the humans, which were considered a contagion.

The Eleventh Doctor's sonic screwdriver picked up strange signals from a little girl who just stood up and staring. When her face turned blue, due to interference, it gave her away as the android, and the Doctor shut her down. She was left lying on the floor afterwards. (TV: The Power of Three)