Few Chinese have heard of Transsion, a Chinese phone maker based in Shenzhen, but the brand has millions of users in Africa, making it one of the most successful on the continent.
"A decade ago, the sales were less than one million, mainly in India and Bangladesh. Transsion became successful only when it put almost all of its attention on the African market," said Chowdhury, who is from Bangladesh.
In 2016, Transsion produced 79.91 million phones, about 80 times the volume ten years ago.
According to technology consultant firm Counterpoint Technology Market Research, Transsion's market share in 2016 was about 40 percent in Africa, beating bigger competitors such as Samsung and Huawei
"Transsion in Africa is like what Nokia was in China years ago. Many people favor it over other phones," said Chowdhury.
"For a company to succeed, we need to find out what exactly people want. African users like selfies, multiple phone card slots, enabling local language, stable music function and longer battery life," he said.
The company organized 200 technicians to improve camera function and calibrate the exposure to suit darker skin tones.
"We have dual-card, triple and even four-card phones, because there are many phone operators in Africa, and it is expensive to dial between networks," said Chowdhury.
Wang Yanhui, secretary-general of Mobile Phone China Association, said Transsion's success is rooted in its dedication to a highly segmented market.
"Many of the Chinese phone makers have explored foreign markets, but many have also failed because they did not work on the brand," Wang said.
Wang said Transsion has had big success selling cheap phones.
"If they want to continue to win, they must work on technology and produce more smart phones," he said.