Gmarket
With such a large selection of goods, it's no surprise that this site is often compared to the Korean version of Amazon. The Korean e-commerce platform Gmarket, whose name literally translates to "global market," sources goods from all across the world. In addition to selling merchandise, this website also hosts virtual auctions. They deal in both common items like furniture and electronics and rare, valuable, and pricey collectibles.
App: iOS/ Android
Website: https://global.gmarket.co.kr