Unusually, I learnt last week that I would have just 24 hours to test the Samsung Galaxy Z Flip, making it nigh impossible to test it fully.

This came after news that the device, Samsung's second foldable smartphone, would go on sale just two days after its official launch at the Galaxy Unpacked event in San Francisco.

Having tried the Z Flip for a day, I conclude that this foldable phone is probably the most polished foldable device on the market yet. It has a smooth folding mechanism that does not feel creaky, unlike last year's Samsung Galaxy Fold.

To prevent dirt and dust from entering the hinge and damaging the display, Samsung has also added tiny nylon fibres in the gaps of the hinge. Both foldable phones, though, are good for 200,000 folds, which works out to 273 folds a day over two years.

But there are concerns about durability as with all folding devices.

Even though Samsung had touted the Z Flip as the first foldable phone to have an ultra-thin bendable glass display, it turns out the Flip's glass display has a layer of plastic on top - confirmed by a Samsung product manager - which is not as scratch-resistant as glass.

The Z Flip has a clamshell design reminiscent of flip phones of the past. It is the second foldable clamshell phone after the new Motorola Razr unveiled in November last year.

When unfolded to its full 6.7-inch screen size, it is slightly taller than a standard smartphone.

It can be tricky to open the Z Flip using one hand as the hinge is relatively stiff. This also means you can open the phone halfway like a laptop and set it on a table to watch videos or make video calls. This clamshell form is also handy for taking photos - as long as there is a ledge or table nearby to place the phone.

In the laptop-like scenario, the interface automatically adapts to make better use of the split-screen form factor - dubbed Flex mode by Samsung. In the Gallery app, for instance, the top half of the screen shows the photos, while the bottom half works like a touchpad for navigation.

Flex mode, which will eventually be available for manufacturers of other foldable Android smartphones, works for the built-in Camera and Gallery apps, the Google Duo video-call app and the Snow camera app. YouTube and Netflix will support this mode soon.

When folded, a tiny 1.1-inch cover display is on the outside of the smartphone. This always-on screen shows the time and a single ticker-tape line of space for notifications. I still have to unfold the phone to respond to text and e-mail messages .

This display can also act as a tiny viewfinder for taking selfie shots with the Z Flip's dual 12-megapixel (MP) rear cameras - located next to the display - when the phone is folded. It is also much easier to hold for taking selfies than a standard smartphone.

The cameras are not as good as the ones in Samsung's latest flagship S20 phones, but the Z Flip takes good photos in most situations, though there is no optical zoom lens. Low-light performance is decent enough - a night mode kicks up the brightness a notch, but the resulting photos still look blotchy.

With a battery capacity of 3,300mAh, the Z Flip will last a day at best. The battery went from fully charged to 49 per cent after about five hours of light to moderate usage.

Aside from its $1,998 price tag, which is costlier than the flagship Samsung Galaxy S20 Ultra, my other reservation about the Z Flip is that it does not bring as much to the table as the Galaxy Fold, which lets you do more with its bigger screen.

You also have to unfold the Z Flip to respond to notifications - perhaps it will work better when paired with a smartwatch.

I am looking forward to Samsung bringing the improvements on the Z Flip to a newer version of the Galaxy Fold.