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UMI Diamond X Black 5" 16GB 4G Dual SIM Unlocked & SIM Free UMI-DX-BLK

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Product Information

Premium in design and premium in performance, introducing the Diamond X from UMi. They say every diamond is unique and that is exactly what you get from the Diamond X.

Enjoy incredible power, performance and more with a smartphone that rivals the top models, but without the high price.

UMi Diamond X


Whether you are browsing the web, scrolling through social media or snapping away, the powerful performance means you can simultaneously listen to music or quickly switch between your different apps.

A combination of the powerful 1.3GHz quad-core processor and 2GB of RAM, the UMi Diamond has speedy loading times and an overall smooth experience.

Store plenty of photos, tracks and more with the 16GB internal memory. Utilise up to 128GB added storage by inserting a micro SD card, if you need more space.


As beautiful and solid as a diamond, the Diamond X features a range of unique design qualities for a one-of-a-kind device. With quality craftsmanship and a custom-made metal frame, the body of this phone features the same strength and class as you get through its performance.

Dual curved to provide a more comfortable grip, the Diamond X has a graceful and elegant shape. Diamond cut, the back cover even features the same sparkle and strength of a real diamond while still delivering a lightweight and premium feel.

UMi Diamond X HD display


Featuring all the qualities of a diamond, it is only fitting that the display is just as bright.

A comfortable size to use and hold, the 5” display delivers a natural viewing experience. Displaying everything in crisp HD, you will enjoy everything from browsing social media to streaming videos.

The SHARP® toughened Dual T2X-1 Glass display has been engineered to offer damage-resistance as well as being slim and light, surviving falls of up to 1.5m if dropped.

UMi Diamond X 8MP rear facing camera, 2MP front facing selfie camera


Capture the moment in crisp, clear detail with the Diamond X’s powerful cameras. The 8MP rear camera is ideal for when you are out and about, so you can achieve those epic shots wherever you may be.

The front facing 2MP camera is perfect for taking selfies and making video calls in good, clear quality.

Powerful performance, 2650mAh Lithium Polymer battery, Android 6.0 Marshmallow


Featuring a powerful high-capacity battery from Sony, the performance of the Diamond X is impressive. The 2650mAh Lithium Polymer battery provides a long-lasting experience throughout the day.

The dual SIM design and 4G capabilities let you connect to two different networks, perfect for balancing work and play or for those trips abroad to avoid high roaming charges.

Intuitive and fully customisable, the Diamond X operates using the Android 6.0 Marshmallow operating system. Make your phone your own by choosing from over 2 million apps from the Google Play Store.



  • Unlocked & SIM Free
  • 4G Ready for the fastest network speeds
  • Ultra-sharp 8 Megapixel rear camera & 2 Megapixel selfie camera
  • 5.0" IPS (2.5D Arc screen)
  • Blazing fast quad core processor + 2GB of RAM
  • Android 6.0 Marshmallow OS
  • 16GB Storage + 128GB micro SD card slot
  • Stylish dual curved design and full-metal frame
  • Large capacity battery

Note: No mains charger included, only USB


Questions & Answers

Customer Reviews

UMI Diamond X Black 5 16GB 4G Dual SIM Unlocked & SIM Free reviews verified by reevooReevoo

Ease of use
Build quality
Value for money
Overall rating
Scores 7.4 out of 10 based on 5 reviews
8 out of 10


Excellent value 4G dual sim phone.
Dropped mine within couple of days of receiving it, screen cracked at edge even though in a neoprene case so maybe not as tough as claimed.
Confirmed purchase: 15 February 2017
Published on: 22 February 2017
7 out of 10


Dundee GB careful purchaser
Value and looks
Confirmed purchase: 07 February 2017
Published on: 19 February 2017
8 out of 10


Surrey GB
Android 6, because of Google's process I cant tell how much was included as it has acquired all my previous apps at install.

Seems to have similar performance to my Elephone which is good as we live in a very weak signal area
Curious having 2 different SIM sizes.
Confirmed purchase: 09 January 2017
Published on: 21 January 2017
6 out of 10


London GB
price and build
4G capability. Only runs 3G in areas my other phone picks up 4G (using same network.
Signal level seems weak
Confirmed purchase: 16 December 2016
Published on: 19 January 2017