Hopline

Chat with everyone around you when there's no signal. Messages hop from phone to phone.

Hopline is an Android app for treks, camps, festivals, fairs, rallies, power cuts — anywhere people with phones have no mobile signal and no WiFi. Phones link to each other directly over Bluetooth / WiFi, and every phone passes messages along for the others, so a message can travel down a line of hikers or across a packed ground, far beyond the range of any single phone. It works the same for five friends or a crowd — the protocol automatically sheds overhead as the group grows (see Built for a crowd below).

No internet. No mobile signal. No account. No server. No hotspot to set up.