TO ANY outsider it looks as if the children have been hypnotised by yet another smartphone game. As the spying elders in a TV ad try to break the spell, the sprogs flash a grin at their screens. “It’s maths, dad,” giggles a fifth-grader to her father. The company behind the ad, Byju’s, sells an educational smartphone app which has been downloaded 14m times since its launch in 2015. Byju’s is one of many education technology (or “edtech”) startups that have emerged in India in the past few years.