In late 2016, India’s richest man, Mukesh Ambani, did something extraordinary: he offered free airtime to everyone and anyone who wanted it. For a limited period, every Indian consumer who signed up to his new Jio phone network could use its 4G and data services without paying a single rupee.

Ambani is not stupid; the owner of Reliance Industries has his fingers in most of the nation’s more lucrative pies. And, true to form, his punt with Jio paid off. After six months, India’s newest mobile phone carrier counted more than 100 million customers (plus, in Aircel and others, a number of bankrupted competitors).

As India Connected explains, Ambani’s bet wasn’t quite as high stakes as first appears. Indians are coming online at a pace of three every second. Today, an estimated 465 million people in India have access to the web, a more than twentyfold increase on 2000: that figure is predicted to double by 2025.

India’s digital revolution is being driven almost exclusively by the smartphone. But what are the effects of this love affair? And, in a country of tight social strictures and long-standing traditions, what changes are these pocket-sized harbingers of modernity setting in motion? It is these questions that Ravi Agrawal, former CNN South Asia bureau chief in New Delhi, sets out to answer in this smart, sympathetic and highly readable account.

India Connected deals with, among other things, the opportunities associated with the smartphone phenomenon, such as their potential to resolve the long-term challenges of gender equality, education for all, and youth employment. Consider the latter. With almost half the population under 25 years old, India needs to create one million new jobs every month just to keep employment rates static. Where government programmes have failed, Agrawal argues, the country’s burgeoning digital economy might just succeed.

Interestingly, all the early running has not been with multinational giants such as Uber or Amazon, but with local start-ups attuned to the foibles of the Indian consumer. So you find India’s most popular smartphone apps – such as the cab-hailing service Ola and TaskRabbit-equivalent UrbanClap – all operating in multiple languages and providing the option to pay in cash. It’s still early days, however: India’s e-commerce market was worth $21bn in 2016, the same as China generates in a single day of online sales.

Agrawal also looks at the more ambiguous impacts of smartphone ubiquity, focusing on social trends and state control. He tackles the first through the lens of dating and marriage, pornography, and internet addiction – issues that exist in the West, but that often play out in unexpected and often curious ways in an Indian context.

Take porn. As Agrawal notes, attitudes to sex in India are still heavily influenced by Victorian prudishness. Couple that with the effects of sex-selective abortion (the ratio between women and men is now 93:100) and you have a widespread problem of sexual repression that the porn industry is feeding off and, arguably, fuelling. Agrawal is too astute to blame smartphones explicitly for the spike in rape cases in India, but nor is he naive enough to think a “free pass to the world of porn” is without consequence.

Agrawal tackles each of his chosen subjects with a reporter’s tenacity and a newshound’s nose. This is both a strength and a weakness. On the plus side, it brings a vitality to his tale as well as a series of strong human-interest threads. So we meet Phoolwati, for instance, a young woman in rural Rajasthan who cycles from village to village evangelising to her sisterhood about the wonders of Google. And Shafiq, a teenager from Srinigar, who invented his own social media platform, “Kashbook”, when the government restricted access to Facebook. And Simran, who met her husband on a dating app after her parents’ efforts at an arranged marriage failed.

Despite these engaging mini-dramas, however, the book’s overall effect is strangely flat. What can work brilliantly for an extended magazine piece does, over the full length of a book, fall into a formulaic pattern – “Vignette; human story(s); expert insights; punchy ending”, and repeat. The result is that Agrawal’s characters often feel more like props than people.

Agrawal’s background at CNN both helps and hinders as well. Unlike most in the press pack, Agrawal (now managing editor of Foreign Policy magazine in the US) takes the time to dig behind the headlines. All the same, many of the subjects – struggles in Kashmir, demonetisation, fake news – are tightly bound to the rolling news agenda, which imposes a thematic predictability and limits the prospect of genuine surprise.

Where this book really shines is when the author lets down his guard a little and shares something of himself. His failed account of trying to catch an Uber in New Delhi, for instance, is both amusing and telling (the driver was digitally illiterate). So too are his memories of the country’s first “feature” phones while a schoolboy in Calcutta. More from his private memory bank would have been good.

After all, Agrawal grew up in India and is a native Hindi and Bengali speaker. This sets him up perfectly to offer the inside account of how Indians see the world in these tumultuous times. And yet, as for how he feels personally about the changes smartphones are bringing or what his instincts tell him about the path ahead, it is difficult to say. Agrawal has written a well-researched book, I only wish he had loosened the grip on his reporter’s pen just a fraction.

Oliver Balch is the author of “India Rising: Tales from a Changing Nation” (Faber & Faber)

India Connected: How the Smartphone is Transforming the World’s Largest Democracy

Ravi Agrawal

Oxford University Press, 240pp, £18.99