Amid internet shutdowns due to protests over Citizenship (Amendment) Act, offline messaging apps such as Bridgefy, Fire-Chat and others are seeing a spike in usage. Both apps use a mesh network, which means that smartphones use short-range Bluetooth connections to form their own network, without the need of net.

from Times of India https://timesofindia.indiatimes.com/india/net-blocked-protesters-use-offline-chat-apps/articleshow/72920823.cms