Add description about running microdroid on cuttlefish
Bug: 182300699
Test: nothing
Change-Id: I6fce53baaf2e9327ebce24c83dab4e2e74f5617f
diff --git a/microdroid/README.md b/microdroid/README.md
index a4fcb12..cb6cc18 100644
--- a/microdroid/README.md
+++ b/microdroid/README.md
@@ -5,7 +5,7 @@
Android, but it is much smaller; no system server, no HALs, no GUI, etc. It is
intended to host headless & native workloads only.
-## Building
+## Building (VIM3L)
You need a VIM3L board. Instructions for building Android for the target, and
flashing the image can be found [here](../docs/getting_started/yukawa.md).
@@ -17,7 +17,25 @@
```sh
$ source build/envsetup.sh
$ choosecombo 1 aosp_arm64 userdebug // actually, any arm64-based target is ok
-$ m com.android.virt
+$ TARGET_BUILD_APPS=com.android.virt m
+$ adb install $ANDROID_PRODUCT_OUT/system/apex/com.android.virt.apex
+$ adb reboot
+```
+
+## Building (Cloud Android)
+
+You may use Cloud Android (cuttlefish) as well. Instructions for running a
+cuttlefish device on your workstation can be found
+[here](https://android.googlesource.com/device/google/cuttlefish/).
+
+The `aosp_cf_x86_64_phone` target already includes the `com.android.virt` APEX.
+So you don't need to build the APEX separately. If you want to rebuild the APEX
+and install it to cuttlefish,
+
+```sh
+$ source build/envsetup.sh
+$ choosecombo 1 aosp_cf_x86_64_phone userdebug
+$ TARGET_BUILD_APPS=com.android.virt m
$ adb install $ANDROID_PRODUCT_OUT/system/apex/com.android.virt.apex
$ adb reboot
```