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Selfie DroneDrone X Pro is a shining star on the drone(无人机) market. Here's why it's gone viral.How does Drone X Pro work?Start by installing the Drone app to your smartphone(Android or iOS). It takes just minutes. After that, just place the battery in your drone and launch the app. You're now ready to fly your Drone X Pro!Why is this drone so special?The drone is about the size of a large screen smartphone. It's so small that it fits into any pocket or handbag!Here's the best part: flying is extremely easy. There's no experience required to fly this drone. You can easily control and fly 12．把下面的长度按照从短到长的顺序排列起来．30厘米    70分米    15毫米    4米    3千米．