Black NUU F4L phone

Reviewing our best selling flip phone – the NUU F4L

What you need to know about NUU F4L

It works on all major carriers in the United States and is sold Factory Unlocked on US Mobile’s website. Since it is based on the Android Go platform, troubleshooting for service issues on the phone becomes really easy. The phone also comes preloaded with Facebook and WhatsApp. NUU F4L supports Voice over LTE Calling (VoLTE) which makes it compatible with US Mobile’s Super LTE SIM and does not compromise on network speeds and call quality.

How is the design? 100,000 flips guaranteed!

The design of the phone is similar to most of the flip phones available in the market. It feels plasticky but it sure is sturdy! NUU’s official website guarantees 100,000 flips for the F4L flip phone. The phone also has 2 rubber mountings below the keypad which prevents the screen from coming in contact with the body.

On the right side, there’s a 3.5mm headphone jack and a USB Type-A charging port. On the left side, you’ll find the volume rockers. When the phone’s lid is closed you’d be greeted with a camera, a cut-out for the noise cancellation microphone, and a flashlight. What’s really interesting is that there are 2 notification lights. One is for messages (which blinks in green) and the other is a notification for battery (which blinks in red when the battery levels are low). 

The main highlight in the front is the secondary display which shows all the important information like date, time, and incoming notifications.

Reviewing our best selling flip phone - the NUU F4L

What about the Display resolution?

The display inside is a 2.8” QVGA display with an aspect ratio of 240*320. The display on the outside is a 1.77” QQVGA display with an aspect ratio of 120*160. The displays are not the greatest or not even close to the modern smartphones but they get the job done just fine.

Notification Lights

There are 2 notification lights found below the camera of the phone. One is for messages, which blinks in green, and the other is a notification for battery, which blinks in red when the battery levels are low. These notifications come in really handy because you would not be tempted to flip open your phone just out of curiosity for notifications.

 Reviewing our best selling flip phone - the NUU F4L

The Camera (s)

You’d find a pair of cameras on the phone which really get the job done. At the back, you’d find a 2.0 Megapixels sensor and upon opening the phone you’d see the front camera on the top-left side. The front camera is a 0.3-megapixel camera which is no way near to today’s smartphone camera standards. But hey, NUU F4L is not a smartphone but a phone for smart people!

Reviewing our best selling flip phone - the NUU F4L

Battery Life 

The battery on the phone is not massive and definitely does not last you weeks of usage like other basic flip phones in the market. NUU F4L comes with a decent 1350 mAh battery which is good for 2-3 days of normal to heavy usage on a single charge. One thing to note is that the battery is removable! 

Connectivity (VoLTE) and Network Bands

This is one of the areas where NUU F4L really outshines the competition. This phone comes with VoLTE (Voice over LTE), WiFi, Bluetooth 4.2 and also has a 3.5mm headphone jack – which is honestly so rare to find in phones in 2021. The network bands on the phone are as follows: 

  • 4G B2/B4/B5/B12/B13/B17/B66
  • 3G 850/1700/1900
  • 2G 850/1900

Social Media – Flip Phone with WhatsApp!

It is absolutely mind-boggling that the NUU F4L not only supports WhatsApp messaging but also supports Video Calling on both the front and rear cameras! This is such a sigh of relief for users who have friends and families overseas and they can chat and talk on video with their NUU F4L. The phone also comes preloaded with Facebook Lite. One thing to note here is that we can not download any other application on the phone as the software restricts the phone from doing so.  

Using a flip phone in 2021?

A lot of us who use a smartphone constantly feel the need to stay up-to-date with social media and the limitless scrolling it has to offer. It almost feels like we are addicted to our smartphones and getting less and less productive. NUU F4L actually solves that problem by giving us the essential applications on our phone combined with the HD Voice calling feature which opens up a lot of possibilities. 

Why buy an NUU F4L from US Mobile?

We offer a wide variety of cellphones on our online store. However, the most popular phone and most in-demand is the NUU F4L because of all the features it has to offer. Additionally, if you purchase an NUU F4L from our store you’d also get FREE Earbuds, FREE US Mobile Starter-Kit, and 2 business day Fast Shipping. The NUU F4L is fully compatible with our Warp 5G and offers exceptional call quality and mobile data speeds. 

Reviewing our best selling flip phone - the NUU F4L



  • Android™


  • MT6731 Quad-core 1.1GHz


  • Inside: 2.8″ QVGA TN 240×320
  • Outside: 1.77″ QQVGA TN 120×160


  • Rear camera: 2.0 MP
  • Front camera: .3 MP


  • Built-in: 4GB
  • RAM: 512MB
  • microSD (supports up to 64GB)


  • 1,350 mAh


  • 4G B2/B4/B5/B12/B13/B17/B66
  • 3G 850/1700/1900
  • 2G 850/1900


  • Bluetooth® 4.2
  • 3.5mm Headset Jack
  • WiFi 802.11 b/g/n
  • VoLTE


  • Vibrator, GPS, Proximity Sensor


  • 109.07 x 57.82 x 21mm


NUU F4L packs all the necessary features required in 2021. The phone is super easy to troubleshoot on especially because it is based on the Android-One platform and all troubleshooting is similar to Android phones. The build quality is not the best but it gets the job done just fine. When holding the phone you would not feel as if it’s a premium device but that’s really not what we’re looking for at this price point. If you’re in the hunt for a budget-friendly phone with 4G LTE Calling, Mobile Hotspot, Video Calling on WhatsApp, and finally hanging up on people like a boss then the NUU F4L is what you need to buy!