Offline Bluetooth messaging

I built a native iOS application that lets nearby phones exchange messages over Bluetooth Low Energy without internet or cellular service. The motivation was access: people should be able to communicate locally even when conventional connectivity is unavailable.

My implementation covers peer discovery, BLE transport, connection lifecycle, and message delivery, with a SwiftUI interface over Core Bluetooth.

Peer discovery

Find nearby devices participating in the communication session.

BLE transport

Carry application messages over a local Bluetooth connection.

Connection lifecycle

Manage the device-to-device connection state that the messaging experience depends on.

Native interface

Present messaging through SwiftUI rather than a web wrapper.

Unlike an internet-backed chat client, the application depends on nearby devices and their Bluetooth connection. Peer availability, connection state, and delivery behavior have to be considered together with the interface.

This work combines mobile product development with device-to-device networking. The practical outcome is a completed messaging application whose local communication does not require a cellular plan or a working Wi-Fi connection.