[5] The novel's action is set in Hounslow, a London neighbourhood, and its main character is a young man, Jas, who joins a gang of Sikh and Hindu youngsters making a living on the side unlocking stolen cell phones.

The novel's language is a mixture of different British dialects (including texting abbreviations), which critics such as Tim Martin ("The addictive exuberance of Jas's patter is also a form of literary prestidigitation"[6]) seem to approve of.

Suhayl Saadi (a writer of Pakistani descent), for instance, praises "the powerful, sometimes homoerotic, depiction of violence and sexual frustration" but notes that the "good" people in the novel all tend to speak in Received Pronunciation accents ("Empathy is created for South Asians only if they speak with a British accent") and this linguistic stereotyping leads Saadi to conclude that Londonstani "is a shabby, 21st-century, Orientalism and is not dissimilar from the mentality via which the Middle East is being re-colonised.

Tim Martin praised the "shattering twist that maintains total narrative cogency while turning the entire book upside down,"[6] but Suhayl Saadi calls it "contrived and unconvincing" and complains of a "clunky" plot.

"[8] Mandy Sayer, writing for the Sydney Morning Herald, praises the novel for exuding a "charming, original energy" but criticizes "the surprise ending and resolution [which] is disappointing, clichéd and trite."

Donald Morrison, in Time, praised the novel's language ("The novel is written in an imaginative mix of English, Punjabi, Urdu, profanity, gangsta rap and mobile-phone texting"[4]) in an altogether positive article.

[11] A full-length review in The New York Times was mixed, criticizing its "teenage flaws" and "an embarrassingly sophomoric twist for a denouement"; still, Sophie Harrison praised its "extra-aural overtones.