After criticism of its plastic designs in the past, Samsung said it had taken a "fresh approach" and used a metal frame, though the back of the phone is still a soft material. Analysts said the decision could help remove the "cheap feel" of previous Galaxy models and firmly position the phone at the high-end.
"The physical design has been a big flaw of its S range having plastics and having a cheap feel. The Galaxy Alpha is an attempt to neuter that negative view of the Galaxy S5's design ahead of the iPhone 6 launch to make that a lot more competitive," Daniel Gleeson, mobile analyst at IHS, said in a phone interview.
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Gleeson added that the fresh design was important as the iPhone 6 was likely to have a bigger screen to match Samsung's model, taking away a "key differentiator".
The price for the Galaxy Alpha has not been set.
Next big release
Samsung is gearing up for another big product announcement in September. The South Korean technology giant released an invited to its "Unpacked 2014 Episode 2" event which will take place on September 3 at the IFA consumer electronics show in Berlin, Germany.
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It is expected to unveil the Galaxy Note 4, a "phablet" device.