I shoot video professionally and I constantly remind myself to use the superior rear cameras on my phone — whether it’s capture on-camera segments of myself or for vlogging. Most people, though, have been conditioned to settle for a ridiculous compromise by choosing the downgraded front-facing camera instead.
Phone makes have led us to believe that the only real solution to this is to switch to foldable phones, largely because their secondary outer displays make it practical to see yourself while using those better cameras. But what irritates me is that many of the best foldable phones cost a fortune — including recent options like the Motorola Razr Fold.
Enter the NUU B40 5G. It's a $249 phone with a god-awful name, but it hides a secret feature that I think all phones should have: a secondary rear screen. After using it for a week, it proves that this simple addition should be standard across the entire industry. Here’s why.
NUU B40 5G |
|
|---|---|
Price |
$249 |
Display |
6.7-inch AMOLED FHD+ (1080 x 2400) |
Refresh Rate |
120Hz |
Chipset |
Media Dimensity 7025 |
RAM |
8GB |
Storage |
256GB |
Rear Cameras |
64MP main (f/1.89), 2MP macro |
Front camera |
16MP |
Battery |
5,000 mAh |
Charging Speed |
35 wired |
Dimensions |
6.39 x 2.91 x 0.33 inches (162.4 x 73.9 x 8.4mm) |
Colors |
Midnight Grey |
Tiny, but functional rear screen
If you look closely at the camera module, you’ll see something peculiar that stands out. It’s actually a secondary screen, dubbed the Vista Display, which is a 1.6-inch AMOLED panel with a resolution of 420 x 228 pixels.
Needless to say, it’s tiny compared to the secondary screens I see on flip-style phones like the Galaxy Z Flip 7 and Motorola Razr Ultra, but my point is that it’s highly effective for exactly what I need. One of the biggest challenges of shooting with a standard slab phone like the iPhone 17 Pro is that I’m usually shooting blind.
Thanks to this preview screen, despite its diminutive size, it still gets the job done almost as well as a foldable phone. Not only can I see myself, but I can also frame the shot exactly the way I want. When I’m ready, I can even start the recording without ever needing to touch the main display. And best of all, it puts out way better results than using the front-facing camera with the selfies I captured above.
Makes selfie screen accessories obsolete
Over the past year, I’ve tried several accessories to solve this problem. It started with the Synco XView M4, a wireless handheld monitor that fastens to the back of my iPhone via MagSafe. However, interference from other Wi-Fi devices constantly caused latency issues, ultimately ruining the experience.
Soon after, I tried a specialty case for my iPhone 17 Pro that featured a built-in rear display. Although the Dockcase Selfix case delivered a reliable live feed, it made my phone incredibly bulky and heavy. Worst of all, it prevented me from using MagSafe wireless charging.
Then came the Insta360 Snap, which combined the best aspects of those previous accessories. But the fundamental issue with all of these solutions is that I am forced to carry them with me everywhere. The NUU B40 5G and its Vista Display solve this entirely because the screen is built right into the phone. It’s always accessible at a moment’s notice — and that is exactly the kind of utility I crave.
A big push to make it standard
I can’t stress the value enough. At $249, the NUU B40 5G packs the modern specs required to compete with the best cheap phones on the market. More importantly, it makes a strong case for making rear displays standard across the board. I get that there are always strict space limitations when designing a phone, but this small addition makes a monumental difference.
Just imagine if future flagships like the iPhone 18 Pro shipped with a rear display because it would instantly offer a compelling reason to skip the rumored iPhone Fold. I don't even want to guess how much Apple's first foldable will cost, but it's guaranteed to dwarf the price of the standard and Pro models.
My only major reservation with the NUU B40 5G is long-term software support. It feels a lot like many of the off-brand devices I test, where ongoing updates are rarely a priority. While it ships running Android 15, I seriously doubt we'll ever see an update to Android 16 on a device like this.
If you aren't strict about having the latest software version, that might not matter. Regardless of its software shortcomings, this budget device proves that a secondary rear screen is a utility every phone needs.
