A short while ago, I came across this Anthony Bourdain piece on the tiffinwalas of Mumbai.
In the BBC, the tiffinwalas may be seeing changes in how they work:
[I]n an attempt to boost awareness about their service they are going a little bit more high tech.
They tiffinwalas have set up a website and an SMS service to increase customer numbers.
This has come as a surprise to many, as many of the lunchbox carriers are illiterate.
Savvy about their business and finance as they are, very few of them have even heard of the internet.
The new technology has been built for them by a software engineer Manish Tripathi who has been adopted as an honorary tiffinwala.