A native bridge enables apps with native components to run on systems with different ISA or ABI.
For example, an application which has only native ARM binaries may run on an x86 system if there’s a native bridge installed which can translate ARM to x86. This is useful to bootstrap devices with an architecture that is not supported by the majority of native apps in the app store (it closes the gap between the number of apps that can be run on that particular architecture).
Starting from L, AOSP supports native bridges (note that it does not provide an actual native bridge).
The libnativebridge library handles loading of native libraries with a foreign ISA (aka translated libraries in the guest environment) into a managed JVM process using the native ISA in the host environment. Note that loading translated libraries and their dependencies in the guest environment is done by a separate linker, which typically uses a different linker config than the host one.
See also design doc (internal only).
