LG's Optimus G, which uses Google's Android platform, will go on sale next week in South Korea for 1 million won ($900), and later in Japan and the United States.
The Optimus G boasts a 13 megapixel camera which a user can instruct to take snaps by talking to it, plus a 4.7-inch screen with a sharper picture quality than both the iPhone and Samsung's Galaxy S III.
Powered by Qualcomm's quad-core Snapdragon processor, the Optimus G will work on superfast mobile networks and be able to carry out several functions at once, such as showing a television broadcast and simultaneously sending text messages or searching the web.
Among its rivals are the Droid Razr models unveiled by Google's Motorola earlier this month, and Lumia 920, a flagship handset made by Nokia and Microsoft Corp which uses the latest Windows Phone operating software.
Apple unveiled its iPhone 5 last week, and said on Monday it had booked orders for over two million iPhone 5 models in the first 24 hours it was on sale, evidence of stronger than expected demand for the new model ahead of the October-December holiday quarter.
Reflecting expectations that the new model will help LG turn around its money-losing smartphone business, LG Electronics stock has risen 20 percent in the past three months, beating a 7.8 percent rise in the wider market and Samsung's 8 percent rise.