docs/deploy/android.md

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# Deploy to Android


## Build model for Android Target

NNVM compilation of model for android target could follow same approach like android_rpc.

An reference example can be found at [chainer-nnvm-example](https://github.com/tkat0/chainer-nnvm-example)

Above example will directly run the compiled model on RPC target. Below modification at [rum_mobile.py](https://github.com/tkat0/chainer-nnvm-example/blob/5b97fd4d41aa4dde4b0aceb0be311054fb5de451/run_mobile.py#L64) will save the compilation output which is required on android target.

```
lib.export_library("deploy_lib.so", ndk.create_shared)
with open("deploy_graph.json", "w") as fo:
    fo.write(graph.json())
with open("deploy_param.params", "wb") as fo:
    fo.write(nnvm.compiler.save_param_dict(params))
```

deploy_lib.so, deploy_graph.json, deploy_param.params will go to android target.

## TVM Runtime for Android Target

Refer [here](https://github.com/apache/incubator-tvm/blob/master/apps/android_deploy/README.md#build-and-installation) to build CPU/OpenCL version flavor TVM runtime for android target.
From android java TVM API to load model & execute can be referred at this [java](https://github.com/apache/incubator-tvm/blob/master/apps/android_deploy/app/src/main/java/org/apache/tvm/android/demo/MainActivity.java) sample source.