I've spent weeks using Microsoft's ambitious new foldable phone with 2 screens — here are the best and worst things about it

Whether I was propping it up like a tent to use as a second screen throughout the day, or holding it like a book to read in Amazon's Kindle app, the Surface Duo's flexible design is easily its best trait.

That's all thanks to the Surface Duo's 360-degree hinge, which enables the two screens to bend all the way back so that the device can assume a variety of poses.

The ability to take on multiple form factors — combined with the extra screen real estate you get from a phone that can bend in half — make the best case yet for why foldable phones should exist in the first place.

The Surface Duo never left me scrambling for a charger. After a full day's worth of use, I still had more than 30% of a charge left the next morning.

It's common for the batteries in high-end smartphones to last for more than a full day, but based on my experience that's an unusually high percentage to have left over.

Of course, it's important to remember that battery life will always vary depending on how you use your device. During my time with the Surface Duo, I primarily used it for checking email, browsing the web, chatting with co-workers on Slack, and streaming video.

With the Surface Duo, Microsoft didn't just join two screens together — it ensured that the software was designed to work smoothly across both displays.

Certain apps like Amazon's Kindle reader and Microsoft's suite of Office tools and apps have been optimized to work especially well on both screens. Kindle, for example, has been updated with a page-turn animation to recreate the experience of reading a hard-copy book. Microsoft's news app also lets you browse headlines on one screen while reading a story on the other.

The Surface Duo's software is generally good at switching between orientations, but there is some lag. This is especially noticeable when using the camera app. Since the Surface Duo's camera is located on the inside of the device, you need to physically flip the device around to switch between selfie mode and world-facing mode. There were several instances, however, where the camera simply didn't know which direction to face, which can be frustrating.

If you take a lot of photos with your phone, the Surface Duo probably isn't for you. The 11-megapixel camera on the Surface Duo is decent, but in my experience didn't take photos that were as sharp, colorful, or crisp as rivals like the iPhone 11 Pro and Samsung Galaxy Z Fold 2.

And for $1,400, you'd want a camera that's at least on par with top-of-the-line phones.

The Surface Duo isn't meant to look or feel like a regular smartphone. But even so, switching from a standard smartphone to the Surface Duo comes with a notable learning curve, especially when using it in public.

The Surface Duo's unusual design means it's much wider than the average phone. It measures 93.3 millimeters across, or 3.7 inches, making it feel daunting at times when you just want to quickly take out your phone, send a quick text, and then put it away. It's also nearly impossible to use it with one hand.

There's a lot of promise in the Surface Duo. After all, we spend most of our days buried in our phones as they've become our lifeline to our social life, work, and much more. So it makes sense that a company like Microsoft that's rooted in productivity would invent a product to help us do more with our phones on the go.

But before a device like the Surface Duo can replace your phone, it needs to do everything equally as well as your phone — including taking photos and offering stable performance when running apps.

The compromises that come with the Surface Duo make it hard to recommend, especially for $1,400. But it certainly makes me excited about where the industry is headed.