How to use browser to show help delivered in apk

I would like to use browser to show html help for my application.

I was planning to send intent like this: How to launch browser to open local file

Here are my approaches I have considered:

1. Copy files to sdcard at installation

   -I don't know. Is it even possible?

2. Store files to assests

   -I don't think browser can access my apps assets

3. Store files to assets and copy them to sdcard when application is started

   -Uggly and no-pro

Any ideas how this should be done right?

1. You can't copy files at installation but you can do it when help button is clicked. But help will be loaded in other application and it may be not very convenient.
2. You can put help into assets folder but other application will not be able to access until you implement your own ContentProvider. But in this case you can show help in your own Activity with a WebView inside.
3. This approach is equal to and more correct than the first one.