Many have installed a PDF reader in their smartphone, but few people know that one of the most popular of these apps comes from a Taiwanese company based in Tainan. Why has it thrived when many others have failed? Taiwanese startups in recent years have set their sights on global markets, but only two app developers have successfully attracted overseas users and scored more than 100 million downloads. One of them is beauty apps developer Perfect Corp., a subsidiary of publicly listed software provider CyberLink Corp. The other is the company housed in the unimpressive building in Yongkang – Kdan Mobile Software Ltd. – which develops tool apps for commercial use.