It is usually difficult to track a person in India, however the Kolkatta police used the mobile phone to track and arrest the former Justice Karnan in Coimbatore according to media reports. The Coimbatore cybercrime cell was using his mobile phone location to find out where exactly he was and they managed to arrest him when he was with an advocate, clearly indicate that mobile phones are to be avoided if a person wishes to remain anonymous.
It is surprising that he did not use the mobile phone of another person, like a close relative or anyone he trusted, he used his own mobile which was tracked very easily after some time.