Best company specialist in product design and development? (China manufacturing)

Hello, I’m looking for recommendations of a company that meets this criterion: specialist in product design and development, at least 5 years in the market, live examples and a focus on China manufacturing.

I already have some options in mind like Titoma, but it’d be cool to have other options to compare, and if you have feedback about Titoma, please let me know!

Thank you all for the help!

What other companies have you researched. Please list them.
What kind of product(s) are you doing?

You know my friend worked at Titoma a few years ago. He told me that Titoma provides electronic design for China manufacturing and delivers reliable products resulting from a proven 10 stage process. They help Western companies with the complete design and manufacturing of custom electronic products. They focus on connected embedded electronics for B2B firms.