India is trying to build what could be the world's largest facial recognition system.
New Delhi says the system could help fight crime and find missing children.
The technology has already been launched at a few Indian airports.
Police in New Delhi says it has identified nearly 3,000 missing children during a trial period last year.
But not everyone is convinced.
Internet freedom advocates say there is little information about where and what the system will be used for and how data will be stored.
The use of facial recognition software is already common in places like China.
But there are questions about how effective it is, with one British study revealing that the technology could be highly inaccurate.
Pranesh Prakash joins Al Jazeera from Bengaluru in India. He is a fellow at the Centre for Internet and Society but is talking to us in a personal capacity.