There is no way to track your smartphone once you lost it, true or false?

You can track your smartphone by an app if you set it up or you can contact your service provider.

If you originally had a tracking device installed on a different device like find my iPhone, you can easily see where it is. If your phone is Android, Google has a system where you can search where's my phone, and if you have your email login into your phone, you can log in on Google and Google will show you where it is.