SHANGHAI--How does a major handset maker go about designing its products? And where does that activity take place? Such locales are typically kept away from prying eyes, but this week ZTE--the world's seventh largest branded handset maker in the fourth quarter of 2009, according to ABI--opened up its research and development center in Shanghai to let reporters explore the company's handset design center, where ZTE handset engineers and designers brainstorm new ideas for mobile phones. Representatives from ZTE explained the company's design philosophy and showed off some concept phones as well. Here's a brief tour of the design center.