Does it really work with no WiFi at all?
Yes. Bluetooth Low Energy is built into every modern phone and needs no network behind it.
Yes. CruiseChattr does not use the internet, ship WiFi, or a cellular signal at any point in delivering a message between two phones.
Bluetooth Low Energy is built into every modern smartphone. Two phones within range of each other can talk directly, with nothing in between. CruiseChattr chains those short hops together, so a message can cross a ship one phone at a time.
The practical limit is range and people. Bluetooth reaches roughly 30 metres in the open — the same venue, or the deck below. Beyond that, the message needs somebody to carry it, which means it moves when people move.
It also works perfectly well alongside a WiFi package. Keep your plan for browsing and calls, and let CruiseChattr handle the messages that need to reach someone in a stairwell.
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