Apple's smartphones are, without a doubt, some of the most popular devices in the world. After years of anticipation, the iPhone 6 made its long awaited debut last year, moving over 10 million units in just the first weekend. Being the cultural icon that it is, many artists and designers love to imagine what the next one will look like. Much like the iPhone 6S Rose Gold Concept we showed you back in March, we have yet another concept of what a future version may look like. With a 4-inch screen and measuring in at just 4.3mm wide, SET Solution has envisioned the smallest and thinnest iPhone yet. Though rumors of a 4-inch edition have been floating around, we'll just have to wait and see. In the meantime, take a look at the awesome iPhone Air concept below.