Bitcoin Light currently integrates Breez SDK Spark for Bitcoin Lightning Network. Breez operates on a hosted LSP model:
a cloud service runs the LN node (via Greenlight), the mobile device holds only keys and signs locally via
defaultExternalSigner. Channel management, liquidity, routing, and watchtower are all handled by Breez.
Fiber is a self-hosted Lightning Network implementation built on Nervos CKB. It can run as a native binary
(fnn), as a native library compiled into mobile apps (via FFI), in WASM via @nervosnetwork/fiber-js,