> ## Documentation Index
> Fetch the complete documentation index at: https://docs.iroh.computer/llms.txt
> Use this file to discover all available pages before exploring further.

# Bluetooth (BLE)

The [iroh-ble-transport](https://github.com/mcginty/iroh-ble-transport) crate
routes iroh over BLE (Bluetooth Low Energy) to allow for P2P connectivity
without the internet.

iroh-ble-transport supports macOS, iOS, Android, and Linux. In the future, it
could support other platforms as well like Windows or Espressif (ESP32 family).

<Warning>
  Both iroh's custom transport API and this crate are experimental. Expect breaking changes.
</Warning>

iroh-ble-transport is open source under the [AGPL
license](https://www.gnu.org/licenses/agpl-3.0.en.html). Commercial licenses are
available for use cases where the AGPL is not suitable. Contact the [number0
team](https://cal.com/team/number-0/iroh-services?overlayCalendar=true) or
[me@jakebot.org](mailto:me@jakebot.org) for details.

## Performance notes

Bluetooth connections on mobile devices typically max out at about \~3-5
connections per device. Per connection, you can expect about 100kbps in decent
conditions, but it's very dependent on the surrounding radio environment
and devices that you're using.

## Usage

```rust theme={null}
use iroh::endpoint::presets;
use iroh::{Endpoint, SecretKey};
use iroh_ble_transport::BleTransport;
let secret_key = SecretKey::generate();

let ble = BleTransport::builder().build(secret_key.public()).await?;

let _endpoint = Endpoint::builder(presets::N0DisableRelay)
    .hooks(ble.dedup_hook())
    .add_custom_transport(ble.as_custom_transport())
    .address_lookup(ble.address_lookup())
    .secret_key(secret_key.clone())
    .clear_ip_transports()
    .bind()
    .await?;
```

## Feature flag

Custom transport support requires the `unstable-custom-transports` feature flag.
The API is unstable and subject to change. See
[#3845](https://github.com/n0-computer/iroh/pull/3845) for background.

```toml theme={null}
[dependencies]
iroh = { version = "*", features = ["unstable-custom-transports"] }
```