Stuart Baggs was found dead by a friend after going to a party the night before, his firm has said, as the cause of his death remains unknown.
The 27-year-old had appeared in “good health” on Wednesday evening as he attended the launch party for his new 4G home-hub product in Douglas, on the Isle of Man.
His body was discovered by his friend in his bedroom at 9am on Thursday morning.
Baggs, who launched his own telecommunications company at the age of 18, was one of the youngest ever contestants on The Apprentice. He became known for his memorable comments on the show, including: "Everything I touch turns to sold" and his infamous introduction, "I'm Stuart Baggs, 'The Brand'".
Baggs' colleagues told The Daily Mail that he had seemed well the evening before his sudden death.
His sister Charlotte said the lack of answers was making it harder for his family to cope. In a tribute on Facebook, she wrote: "Today my dearest brother Stuart Baggs gained his wings. To say we are all shocked and devastated is an understatement.
"Love him or hate him, he touched many people's lives from his TV antics to his amazing work with BlueWave Communications. This week he unveiled plans that would have revolutionised the industry, now our world has been shattered apart.
“Can't explain how proud I am of him. He was the king of following his dreams and making them happen. Not knowing what or why makes it all the harder."
Lord Sugar paid tribute to Baggs on Friday, praising him as one of the "stand-out" contestants of the whole programme.
A police spokesperson said there was nothing to indicate that his death was “criminally suspicious”.
