Hi Hong,
Good to hear, but it is a system behavior, I don't think it can be accessed from WinRT API.
If you want to modify the app name, simply change it from appmanifest app name should be ok.
--James
<THE CONTENT IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, WHETHER EXPRESS OR IMPLIED>
Thanks
MSDN Community Support
Please remember to "Mark as Answer" the responses that resolved your issue. It is a common way to recognize those who have helped you, and makes it easier for other visitors to find the resolution later.