Apple Inc has launched its long-awaited watch, including yellow or rose gold models with sapphire faces costing up to $17,000, but some investors questioned whether Chief Executive Tim Cook’s first product would be a breakaway hit. Apple’s first new device since Cook became CEO will be available for order on April 10 and in stores on April 24, including chic boutiques in Paris, London and Tokyo. All the watches share digital faces that can look like traditional time pieces, show the heartbeat of a friend, and display photos and interfaces for apps. Apple also is offering researchers new development tools, called Research Kit, to help medical researchers design apps for clinical trials. The Apple Watch sport will start at $349 for the smaller, 38-mm model. The standard version of the watch will start at $549 and the high-end “Edition” watch will be priced from $10,000.