The highly popular HTC has an all aluminium back, prior versions of the Sony smartphone had glass fiber polyamide.
The new Sony Xperia Z1 is similar in appearance and design to the Xperia Z where the Xperia Z used glass fiber polyamide in the construction of its frame, the Z1 switches to an aluminum frame that runs the outside edges of the device, complementing its glass front and rear panels.
Electronista said that the fundamental design materials are very similar to Apple's iPhone 4 and 4S, which also used an aluminum in its construction, along with glass front and rear panels, even if their appearances are distinctively different.
What is not clear is whether the Sony Xperia Xperia Z1 uses its metal frame to function as part of the antenna as in the iPhone 4 and 4S. Apple switched to a largely aluminum rear panel in the iPhone 5 to help reduce weight, although it is still considered a premium product. Sony has been switching to higher quality materials in its devices over the course of 2013, as it seeks to differentiate itself as an Android maker from Samsung, which still continues with largely plastic designs in its flagship models.
The Xperia Z1 is also water and dust resistant and has Gorilla Glass 3. The front is protected by Dragontrail glass, the same as used on the Xperia Z Ultra. Like the Xperia Z Ultra, the Sony Xperia Z1 will be powered by a Qualcomm Snapdragon 800 quad-core processor clocked at 2.3GHz and paired to an Adreno 330 GPU, while it will also feature a 20.7-megapixel camera with a discrete BIONZ image processing chip.