New Delhi, Sept. 5 -- Murali Neelakantan, 52, has a set system for Saturday evenings. The Mumbai-based retired lawyer plays volleyball with his neighbours, a game that requires at least eight players. The group coordinates on WhatsApp, but Murali, who refuses to use the app, has his own arrangement. "Every Saturday morning, someone posts in the group to check who's in for the evening. Once they get a sense, one of them messages me via SMS: just a simple '5?'" he says. "If I reply 'yes,' I'll get another message later saying 'game on.' That's all I need."

It is, as he admits, "annoying for them," but the system has worked for a decade. To him, it's proof that connection doesn't have to be mediated by endless notifications. "If someone rea...