Oppo could threaten Samsung's global dominance in the nascent Foldable category. Samsung's poised to unveil the successors to the Galaxy Z Fold 4 (left) and Galaxy Z Flip 4 (right) at its Unpacked event on Wednesday. In the four years Samsung has been making foldable phones, the company has managed to overcome technological hurdles to dominate the category, sell tens of millions of foldable devices, and raise the bar for mobile innovation worldwide. But as the South Korean electronics giant gears up to launch its next wave of foldable phones at Galaxy Unpacked this week, it faces a decidedly more crowded landscape.In the US this year, both Google and Motorola launched compelling foldable phones that run in direct competition with the Galaxy Z Fold 4 and the Galaxy Z Flip 4. And now Oppo subsidiary OnePlus is also rumored to have a foldable Phone on the way. Outside the US, however, Samsung contends with a growing rivalry from Chinese phone manufacturers Oppo, Honor, and Huawei -- all of which released their latest foldable phones internationally to compete with Samsung.Samsung's early investments into foldable phones mean that even as competitors enter the space, it'll maintain a lead in software optimization, durability and support, as one research firm points out. "Globally, there is no single challenger, although Chinese vendors collectively are starting to offer worthy alternatives -- especially for the domestic Chinese market," Avi Greengart, analyst at Techsponential said to CNET in an email. "Honor is offering extremely advanced hardware, and Oppo's Find N series provides a different form factor to the Galaxy Z Fold at a lower price," Greengart added.Earlier this year, Oppo launched its first-ever flip phone in overseas markets beyond its native China. Although the Find N2 Flip appears to be heavily inspired by its Samsung counterpart (even down to the lavender color option), it still drew praise from consumer tech reviewers, including myself, for its vertical cover screen. The Find N2 Flip's 3.26-inch cover screen is more usable than the visibly smaller display (1.9-inch) on the Galaxy Z Flip 4, although it might not look as elegant. During my time with the Find N2 Flip, I found the cover screen convenient for checking the weather and taking selfies without needing to unfold the phone. I also enjoyed using the quick replies feature from the cover screen, which let me respond to WhatsApp or Slack messages with a set of prewritten templates. Oppo's Find N2 Flip is its response to Samsung's Galaxy Z Flip 4. But it's not available in the US.But in its current form, the Find N2 Flip is still limited in its functionality. You can't open any app from the cover screen, so you'll have to unfold the device for that. By comparison, Motorola's 2020 Razr has a full keyboard for typing and it allows you to curate apps suited for the cover screen (such as Gmail and YouTube). You can even play games, including PUBG mobile, if you so please. Among Samsung's competitors, however, Oppo is the rival with the most potential to compete with Samsung in the foldables segment. That's according to research firm International Data Corporation, which cites a number of reasons including growth trajectory, market footprint and marketing efforts. "It's still early to say who will have tight competition with Samsung. But Oppo seems to have found a good formula," said Will Wong, senior research manager at IDC. "Of course, the gap between the two brands is still significant as Oppo still requires a strong premium brand name to better appeal to consumers."Oppo-branded stores are open in more than 70 countries and territories, according to Wong, which gives the Chinese company a competitive edge over its homegrown rivals -- it even threatens Google, which has a presence in 20 countries and territories. These physical stores or booths are especially important for foldable phones considering the foldable category is still relatively new."Having a wider retail or offline store network for the consumers to easily access and feel, touch, and experience the products before buying them is crucial," said Wong. "Thus, Oppo has a bigger chance of gaining market size, especially if it manages to build a high-end image," In the first quarter of this year, Oppo's market share surged to nearly 17%, putting it in second place worldwide behind Samsung, which commands 64.5% market share, according to IDC's Wong. Meanwhile, Huawei holds 10% of the global market, while Honor has captured 4% and Motorola accounted for less than 1%."We want to make a stride in the premium sector, especially the foldable phone sector, as Oppo believes foldable phones provide more diversities and flexibility for consumers' lives," Elvis Zhou, Oppo's overseas chief marketing officer, told CNET in an email in June.The Galaxy Z Flip 4 has a 1.8-inch cover screen, but Samsung is expected to make that external screen larger in its next flip phone lineup.The Find N2 Flip is the crown jewel of Oppo's marketing blitz for its smartphone division. The Chinese company is striving to build an upscale brand globally and capture a larger slice of the foldable phone pie. As part of that strategy, Oppo pulled out all the stops to keep its brand at the forefront of people's hearts and minds globally. One key marketing focus is high-profile sporting events, where Oppo has partnered with Wimbledon, arguably the most prestigious tennis tournament on the circuit, and more recently the UEFA Champions League. Together the two prestigious tournaments attract a worldwide audience estimated in the hundreds of millions."Being a part of the most exhilarating sporting tournaments and competitions is very important to Oppo," Zhou told CNET in an interview ahead of Wimbledon. "The international influence and local appeal of sporting events will not only help to enhance Oppo's global brand influence but also help to create an emotional connection with local users."Oppo appointed Brazillian soccer legend Kaka as its global brand ambassador. It also teamed up as a sponsor with the UEFA Champions League as part of its global brand-building campaign. Clamshell-style phones have accounted for more than 50% of foldable shipments from 2020 through to the first quarter of 2023, IDC told CNET in an email. This trend is unlikely to change, the research firm says, since the average selling price of a flip phone is generally lower than a book-style phone. "Launching a book-style foldable will be a plus point as it can help Oppo better target a different segment like businesspeople or professionals," Wong said. Although Oppo has released at least two book-style models in China (the Find N and the Find N2), it doesn't have a response, at least globally, to Samsung's book-style phones. The company will likely announce its next-generation Find N3 Flip later this year or early next year, if rumors turn out to be accurate. But before then, Samsung could raise the bar for flip phones everywhere when it debuts its fifth wave of foldable phones tomorrow. "We'll have to see how Samsung responds with the Galaxy Z Flip 5, but, at this point, anything that brings consumers to consider foldables -- even if it's solid competition -- is good for Samsung." Greengart said.