Nearby Connections
Nearby Connections is a Google API, built for Android with a more limited iOS library, that lets nearby devices discover and connect to each other and exchange data directly, without internet. It abstracts several radios, including Bluetooth and WiFi, and picks among them to establish a peer-to-peer link for local messaging and file transfer. It is a direct-link building block for device-to-device communication rather than a full multi-hop mesh protocol.
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 built for Android. Google also ships an iOS library, but on Apple platforms Google's repository lists Wi-Fi LAN as the only supported medium, so an iPhone and an Android phone connect only when both are on the same Wi-Fi network. 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 first, 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-first connectivity primitive, while Offline Protocol is a cross-platform mesh protocol with routing, identity, and encryption built in. See peer-to-peer mesh networking.
Frequently asked questions
What is Google Nearby Connections used for?
It lets nearby devices, mainly Android, discover, connect, and exchange data directly over Bluetooth and WiFi with no internet, powering features such as local file sharing, nearby collaboration, and local multiplayer.
Does Nearby Connections work on iOS?
Partly. Google ships an iOS library, but on Apple platforms its repository lists Wi-Fi LAN as the only supported medium, so the iPhone and the other device must share a Wi-Fi network, and Bluetooth is not listed as implemented there. A cross-platform mesh such as Offline Protocol runs on both iOS and Android and connects phones over BLE with no shared network.
Is Nearby Connections a mesh network?
Not a full one. It establishes direct connections between devices in range rather than routing traffic across many intermediate hops. Building a routed multi-hop mesh on top of it is additional work, which a mesh protocol like Offline Protocol provides directly.
