The third OnePlus Android phone , the OnePlus X (aka OnePlus Mini), is now available invite-free forever. In this article we detail everything you need to know about the OnePlus X, including its price, specifications and features. Also read our OnePlus X Onyx review and OnePlus X Champagne review.

Previously known as the OnePlus Mini, the OnePlus X is indeed a smaller version of the OnePlus 2, complete with the new Alert Slider. Except it's had something of a redesign, losing the sandpaper-effect rear cover and here available with either a black glass or ceramic build.

Contrary to rumours, rather than adding the features missing from the OnePlus 2, such as NFC, the OnePlus X removes more of them - the fingerprint scanner and USB-C port are all gone. The processor, graphics and memory have been downgraded, and the screen has shrunk down. But the OnePlus X is also cheaper than the OnePlus 2, of course, and it adds what may prove to be a better camera and support for microSD.

OnePlus says its new smartphone is a "design-centric" device, which is "chic and powerful enough to fit any lifestyle". We'll look more into what that entails below. Also see: Best phones 2015 & Best Android phones 2015.

OnePlus X UK release date, price: How much is the OnePlus X?

The OnePlus X is already on sale in the UK and, as of January 2016, available to buy invite-free from OnePlus' site.

The OnePlus X is also available through third-party grey-market sites, eBay or Amazon

The OnePlus X went on sale on 5 November 2015 at £199/269 EUR (19 November at $249 in the US), while the Ceramic OnePlus X went on sale in the EU and India on 24 November at £269/369 EUR. If you fancy the Ceramic version you'll need to get in quick, though - only 10,000 are being made. Also see: OnePlus One, OnePlus 2 & OnePlus Power Bank reviews.

How to buy a cheap OnePlus X

Now that the OnePlus X is available invite-free you don't need to follow the route we explain here in order to get hold of one in the UK. However, you may still be able to save some money, so it's worth checking out.

Geekbuying, a Chinese site that imports phones to the UK, is selling both the Onyx and Champagne models for £192.48 and £185.37 respectively with free shipping, but note that you may have to pay import duty on top of this price (also see our grey-market tech buying advice).

It's worth pointing out that the OnePlus X sold by Geekbuying is the Chinese model, and does not support the 800MHz 4G LTE band. This means O2 users will not be able to connect to a 4G LTE network using this model. The 1800- and 2600MHz bands are supported, so users of other UK mobile networks should be fine. Also see: How to tell if a phone is supported by my network.

OnePlus X design

As we mentioned above, two variants of the OnePlus X will be available. The OnePlus X Onyx is a premium-looking phone with glossy mirror-like black glass on a metal bezel. It has slightly rounded edges, and at just 140x69x6.9mm and 138g is the slimmest and lightest OnePlus phone in the range. Also see: Best new phones coming in 2015/2016.

The OnePlus X Ceramic edition has a scratch-resistant design that for each model is 25 days in the making - OnePlus calls it a feat of engineering and design. Slightly chunkier than the Onyx glass version, the OnePlus X Ceramic weighs 160g.

Both models have a brushed anodized metal frame etched with 17 microcuts. They feature the Alert Slider added to the OnePlus 2, allowing you to set the priority level for notifications without taking the phone out of your pocket. A power button and volume rocker sit on the device's opposite side.

OnePlus X specifications and features - what to expect from the OnePlus X

Unlike the OnePlus 2, the OnePlus X is not designed to have class-leading performance. Inside there's a 2.3GHz Snapdragon 801 quad-core processor, 3GB of RAM and Adreno 330 graphics. You can bolster the 16GB of built-in storage with a microSD card up to 128GB in capacity, or you can use that slot to add a second Nano-SIM card.

Smaller than the OnePlus One and OnePlus 2 phablets, the OnePlus X has a 5in full-HD (1080p) AMOLED screen with a pixel density of 441ppi. This is an ambient display that will wake in 'duochrome' mode to alert you to notifications. A proximity sensor also wakes the screen when the phone is removed from a pocket or bag. Also see: OnePlus One vs OnePlus 2.

The OnePlus X features a 13Mp rear camera, with f/2.2 aperture, optimised white balance and saturation, and a fast 0.2-second autofocus with phase detection. There's also an 8Mp selfie camera at the front.

OnePlus preinstalls its own OxygenOS operating system, which is based on Android 5.1.1 Lollipop. It includes onscreen gestures, a file manager and custom quick settings, plus an FM radio.

OnePlus X models: Ceramic, Onyx
OnePlus X operating system: OxygenOS based on Android 5.1.1 Lollipop
OnePlus X processor: 2.3GHz Snapdragon 801, quad-core
OnePlus X graphics: Adreno 330
OnePlus X memory: 3GB LPDDR3 RAM
OnePlus X storage: 16GB, plus up to 128GB microSD
OnePlus X screen: 5in full-HD (1920x1080, 441ppi) AMOLED, Gorilla Glass 3
OnePlus X cameras: 13Mp rear, f/2.2 aperture, 1080p video/120fps slo-mo at 720p; 8Mp front, f/2.4 aperture
OnePlus X sensors: Accelerometer, gyroscope, proximity, ambient light, hall
OnePlus X battery: 2,525mAh non-removable lithium-polymer (charges over Micro-USB)
OnePlus X connectivity: 4G bands 3, 7 & 20 (EU & Asia model); dual-Nano-SIM (one SIM slot can be used for microSD card); 2.4GHz 802.11b/g/n Wi-Fi; Bluetooth 4.0; GPS; GLONASS
OnePlus X audio: Bottom-facing speaker; dual-mics with noise cancellation; 3.5mm headphone jack; FM radio
OnePlus X dimensions: 140x69x6.9mm
OnePlus X weight: 138g (Onyx), 160g (Ceramic)

OnePlus X pictures

First, the Onyx black glass OnePlus X:

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

OnePlus X Onyx picture

Second, the limited Ceramic OnePlus X:

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

OnePlus X Ceramic picture

Read next: OnePlus 2 review: A magnificent smartphone, and not just 'for the money'

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