Xiaomi Mi MIX 3 Review: The Sliding Smartphone Revolution

Xiaomi Mi MIX 3: Sliding Full-Screen

The Xiaomi Mi MIX 3 is a flagship Android smartphone released by Xiaomi in October 2018, positioned as the third generation of the revolutionary Mi MIX series. Its defining feature is the sliding full-screen design—a mechanical slider mechanism that hides the front camera module, eliminating notches or punch holes and achieving a nearly 100% screen-to-body ratio. This design was a milestone in Xiaomi’s pursuit of bezel-less display technology, setting it apart from mainstream smartphones of the era.

Core Design & Sliding Full-Screen Mechanism

The Mi MIX 3’s most iconic trait is its magnetic sliding structure, which replaces traditional notch displays with a retractable front camera setup:

Mechanical Slider PrincipleThe phone’s upper half (housing the front camera and earpiece) slides vertically upward along precision rails, powered by a set of neodymium magnets that ensure smooth, stable movement. Xiaomi claimed the slider could withstand 300,000+ sliding cycles (equivalent to 5 years of daily use), addressing durability concerns for mechanical components.
Full-Screen Display Specifications
- 6.39-inch Super AMOLED panel with FHD+ resolution (2340×1080 pixels) and 403 ppi.
- 19.5:9 aspect ratio, 93.4% screen-to-body ratio—a leading figure in 2018.
- Support for DCI-P3 wide color gamut and HDR10, delivering vibrant visuals for media consumption.
- Gorilla Glass 5 protection for scratch resistance.
Design AestheticsThe back cover uses 3D curved glass with gradient color options (Midnight Black, Sapphire Blue, Emerald Green), paired with an aluminum alloy frame for a premium, ergonomic feel. The sliding mechanism adds a tactile “click” feedback, enhancing user interaction.

Key Hardware Specifications

Component Category	Detailed Specifications
Processor	Qualcomm Snapdragon 845 (10nm manufacturing process); octa-core architecture (4×Kryo 385 Gold @ 2.8GHz + 4×Kryo 385 Silver @ 1.8GHz); Adreno 630 GPU for gaming and graphics rendering.
Memory & Storage	Multiple configurations: 6GB/8GB/10GB LPDDR4X RAM; 128GB/256GB/512GB UFS 2.1 storage (no microSD card expansion support).
Camera System	Rear Camera: Dual-camera setup (12MP Sony IMX363 main sensor, f/1.8 aperture, 1.4μm pixel size, OIS + 12MP Samsung S5K3M3 telephoto sensor, f/2.4 aperture, 2× optical zoom). Supports 4K video recording at 60fps and portrait mode with background blur.Front Camera: Dual 24MP Sony IMX576 sensors (f/2.0 aperture) for high-resolution selfies and portrait shots, enabled only when the slider is open.
Battery & Charging	3200mAh non-removable lithium-ion battery; supports 18W Qi wireless charging (a first for the Mi MIX series) and 18W wired fast charging via USB-C port. No reverse wireless charging feature.
Connectivity & Sensors	4G LTE Cat.18 (up to 1.2Gbps download speed); Wi-Fi 802.11 a/b/g/n/ac (2.4GHz/5GHz); Bluetooth 5.0; NFC (for Mi Pay and contactless payments); GPS/GLONASS/Galileo; infrared blaster for smart home control.Sensors: In-display fingerprint scanner, accelerometer, gyroscope, proximity sensor, ambient light sensor.
Durability & Extra Features	IP53 splash resistance rating (protects against light rain and splashes); stereo speakers tuned by Dirac; no 3.5mm headphone jack (supports USB-C audio and Bluetooth audio).

Software & User Experience

Initial OS: Launched with MIUI 10 based on Android 9 Pie, featuring a minimalist UI optimized for the full-screen display, gesture navigation, and AI-powered features (e.g., AI scene recognition for cameras).
Software Updates: Xiaomi released major OS upgrades up to Android 10 with MIUI 12, followed by security updates for a limited period. The device did not receive Android 11 or later versions, consistent with Xiaomi’s update policy for 2018 flagships.
Slider-Centric Features: Customizable shortcuts (e.g., open the front camera, launch flashlight, or activate voice assistant) by sliding the mechanism, adding a layer of interactive convenience.

Target Markets & Positioning

The Mi MIX 3 was targeted at tech enthusiasts and design-conscious users who valued bezel-less displays and innovative mechanical structures over incremental hardware upgrades.
A special 5G variant (Mi MIX 3 5G) was released in early 2019, becoming Xiaomi’s first 5G-enabled smartphone and targeting markets with emerging 5G infrastructure.

Advantages & Limitations

Advantages	Limitations
Revolutionary sliding full-screen design with 93.4% screen-to-body ratio, no notches or punch holes.	Relatively small 3200mAh battery leads to average battery life (~6–8 hours of screen-on time).
Smooth magnetic slider mechanism with high durability (300,000+ cycles).	Mechanical structure adds thickness (8.46mm) and weight (218g) compared to non-slider flagships.
Dual front cameras for high-quality selfies and portrait mode.	No expandable storage; limited internal storage options for heavy users.
Support for wireless charging and infrared blaster for smart home control.	IP53 rating offers only basic splash resistance, not full waterproofing.
Flagship Snapdragon 845 performance for gaming and multitasking.	Outdated software support (stopped at Android 10/MIUI 12).

Legacy & Significance

The Mi MIX 3 marked the peak of Xiaomi’s mechanical sliding design experiment. While the slider solved the full-screen vs. front camera dilemma in 2018, it was later phased out as punch-hole displays and under-display cameras became mainstream solutions for bezel-less smartphones. The device remains a memorable example of Xiaomi’s willingness to explore innovative form factors to stand out in the competitive flagship market.