Moto X, available in a range of colours and materials, will be Motorola's first flagship device since Google purchased it in 2012, and aims to topple Samsung's Galaxy S4 and Apple's iPhone not through advanced features but instead through personalisation and customisation.

Using the MotoMaker.com website, users will be able to choose from almost two dozen colours, and select materials like wood for the backing. Purchasers will also be able to engrave a message or name on the back of the device, as well as customise a special welcome message for whenever the phone's turned on.

According to Motorola the device will run Android 4.2.2 at launch, and sports the new Motorola X8 mobile computing system that comes with several chips: a 1.7GHz Qualcomm Snapdragon S4 Pro, as well as a natural language processor and a contextual computing processor that deals with the sensors. 

Rick Osterloh, Motorola's senior vice present of product management, said the system "makes new and cool things happen at very, very low power." The Moto X boasts a 24-hour battery life, or 13 hours of talk time, with its 2200mAh battery.

The Moto X also comes equipped with a 4.7-inch, 1,280-by-720 display with 316 pixels per inch, and Osterloh told reporters his company spent time "studying peoples' hands" to see which size feels most comfortable in the hand.

"Our primary goal was comfort," Osterloh said, adding that the phone "was the one the majority of smartphone users wanted to carry." Motorola also got as much screen "as humanly possible" on the device and finished with a display that covers over 70% of the surface of the phone, he said.

The company said its Moto X will go on sale in the US at the end of August for a suggested retail price of $US199.99, to customers who sign a two-year contract. There is no word yet on an Australian release date and price.

Analysts said the phone's customization options are a novel touch which may appeal to fashionistas, but some are questioning whether it'll be enough.

"We would have expected magic from somebody like Google, and this is not magic," Roger Entner, an analyst with Recon Analytics, told Reuters.

"Motorola could have done this without Google equally well. Or for that matter, another hardware manufacturer not owned by Google could have made this phone," he said, citing the phone's average hardware specifications.

Meanwhile Colin Gillis, an analyst with BGC Partners, told Reuters he thought the Moto X is too expensive given the market's shift to lower-priced phones. Motorola is "chasing after the high end right when the high end is dead," he said.

The phone's price and its lackluster features will hamper Motorola's efforts to return to profitability, said Gillis.

"Motorola has been in the money-losing club and clearly they want to stay there," he said.