Nearby Connections

How it works

Nearby Connections handles the mechanics of finding and connecting to nearby devices. One device advertises and another discovers it, and once they agree to connect, the API establishes a link over whichever underlying radio it selects, such as Bluetooth or WiFi, so the developer does not manage each radio directly.

It supports different strategies for one-to-one and one-to-many connections and provides encrypted payload transfer between connected devices. The connections it forms are direct links between devices that are in range of each other.

It is an Android platform API, so it is available on Android devices and does not by itself span iOS. It also focuses on establishing direct connections rather than routing traffic across many intermediate devices, so building a large multi-hop mesh on top of it is additional work.

Why it matters

Nearby Connections lowers the barrier to offline, device-to-device features on Android: sharing files, local multiplayer, and nearby collaboration without a server. Abstracting the radios saves developers from handling BLE and WiFi separately.

Its scope also defines its limits. It targets Android, forms direct connections rather than a routed multi-hop mesh, and is a platform API rather than a cross-platform protocol with its own identity and delivery guarantees.

How it relates to Offline Protocol

Offline Protocol operates at a higher level and across platforms. Its mesh, DORS, runs on both iOS and Android, combines BLE, WiFi Direct, and the internet with automatic failover, and relays up to 8 hops with acknowledgment, retry, and deduplication, rather than forming only direct links. It adds Ed25519 identity, MLS (RFC 9420) encryption, and serverless service discovery as part of the protocol.

In short, Nearby Connections is an Android connectivity primitive, while Offline Protocol is a cross-platform mesh protocol with routing, identity, and encryption built in. See peer-to-peer mesh networking.