Interesting, but this depends on so many factors - the type of brand, Tesla launching a mobile phone or Emmanuel launching a mobile phone. Tesla has a brand already and it will be easier to build on the existing brand value. What type of product? Who are the target audience.
The best answer I can give to this is media planning - right message to right people through the right media and the right time and in right place. Provided you can get all these five things things right, you should be fine.