One of the most fascinating parts of a phone's design process is the concept drawing stage, where a manufacturer first experiments with ideas before deciding on a firm design and feature set. Ahead of today's ASUS ZenFone 6 launch, we visited the company's headquarters in Taipei, Taiwan, to get an early look at the finished article, as well as some of the design iterations that led there.

ASUS showed us a wealth of concept drawings, as well as dummy units of some of the more advanced designs, which we present below for your viewing pleasure.

Behold: a gallery of things, most of which are not the ASUS ZenFone 6.

ZenFone 6 concept

This concept shows an early hinge-based flip camera with more angular chassis design.

ZenFone 6 concept

ASUS experimented with a possible third rear camera, likely telephoto, in addition to the two main reversible shooters. One concept imagined the camera mechanism also doubling as a kickstand. (You can't do this with the real ZenFone 6. We tried; it fell over.) These shots also show several other flip camera designs.

ZenFone 6 concept

A very different flip camera design is seen here, along with a softer overall phone body that resembles some of LG's older designs.

ZenFone 6 concept

A variation on the final ZenFone 6 design shows a darker color palette with an ostentatious gold trim.

ZenFone 6 concept

A possible quad camera design is shown here, as part of a wider flip camera setup.

ZenFone 6 concept

Even the small details go through multiple levels of refinement on the road to launch. Alternative power and volume keys are shown above.

ZenFone 6 concept

A close-up of a flip camera design much closer to the finished model. (Some early ZenFone 6 prototypes we saw still used the "Reverso" moniker.)

ZenFone 6 concept

Another variation on a three-camera design with two flip cameras. This one shows a much smaller reversible module off to the right side of the device.

ZenFone 6 concept

In these sketches, we see the final design of the ZenFone 6 taking form.

From concept drawing to dummy unit. This off-center notch eventually leaked online as a possible ZenFone 6 model, but in reality, never made it past the prototyping stage.

ZenFone 6 concept

One of the most fascinating prototype designs shows a removable, rotating module that would plug into the top of the phone, housing the camera and an OLED strip for showing signal data, time and other info.

ASUS slider

Another oddity: This dual slider design with cameras up top, and what appears to be a secondary screen area down below.

ZenFone 6 concept

Other designs were also made into dummy devices, including this wacky curved model.

Most phones exist in several disparate forms before the manufacturer decides on a final design. It's rare, however, to have such an in-depth look at the countless different versions of ZenFone 6 that existed on paper and in model form before ASUS decided on its final design. Which is your favorite? Hit the comments and let us know!

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