Aarogya Setu, India's COVID-19 contact tracing app, came under significant criticism and scrutiny for collecting huge amounts of data and concerns about its weaponisation.

The app was made mandatory for millions of Indians, including government employees and workers in some private companies, making india the only democratic nation to mandate a contact tracing app on such a large scale.

However, critics argued the app collected excessive personal data, including name, phone number, gender, travel history and whether someone is a smoker. Concerns were also expressed about its closed nature, seen to protect its inner workings and data handling practices from outside view. 

The fact that the app also stored location data and required constant access to the phone's Bluetooth prompted complaints about its invasive nature.

Civil liberties groups launched legal challenges against the mandatory use of the app, arguing it is illegal in India to criminally prosecute people for not installing a smartphone application.

The Indian government maintained that the app was necessary to effectively track and trace COVID-19 cases, and that user data was processed anonymously and securely.

But privacy advocates remained unconvinced and continued to push for greater transparency and voluntary usage of Aarogya Setu, persuading authorities to release the source code of the Android app.