ZTE nubia Z20 vs Asus ROG Phone II: Which Gaming Phone Lasts Longer?

Both the ZTE nubia Z20 and the Asus ROG Phone II represent a fascinating period in gaming phone development, leveraging the Snapdragon 855+ to deliver high performance. However, they approach the gaming experience from slightly different angles. The nubia Z20 aimed for a more versatile dual-screen experience, while the ROG Phone II doubled down on gaming-centric features. This comparison dissects their key differences, focusing on battery life, charging, and overall performance to determine which device offers the best experience for demanding users.
Phones Images

🏆 Quick Verdict

For the average user prioritizing sustained gaming and slightly faster charging, the Asus ROG Phone II emerges as the winner. Its 114-hour endurance rating, coupled with 30W charging and Quick Charge 4 support, provides a tangible advantage over the nubia Z20’s 100-hour rating and 27W PD2.0 charging.

PHONES
Phone Names ZTE nubia Z20 Asus ROG Phone II ZS660KL
Network
2G bandsGSM 850 / 900 / 1800 / 1900GSM 850 / 900 / 1800 / 1900
3G bandsHSDPA 850 / 900 / 1700(AWS) / 1900 / 2100HSDPA 850 / 900 / 1900 / 2100
4G bands1, 2, 3, 4, 5, 7, 8, 18, 19, 20, 26, 34, 38, 39, 40, 41 - EU/Asia1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 28, 29, 32, 34, 38, 39, 40, 41, 46
SpeedHSPA 42.2/5.76 Mbps, LTE (6CA) Cat18 1200/150 MbpsHSPA 42.2/5.76 Mbps, LTE (5CA) Cat18 (Cat20 Ultimate edition) 1200/150 Mbps
TechnologyGSM / CDMA / HSPA / EVDO / LTEGSM / HSPA / LTE
 1, 2, 3, 4, 5, 7, 8, 12, 17, 18, 19, 20, 25, 26, 28, 30, 34, 38, 39, 40, 41, 66 - NA-
Launch
Announced2019, August. Released 2019, August2019, July 22. Released 2019, September
StatusDiscontinuedDiscontinued
Body
BuildGlass front (Gorilla Glass 5), glass back (Gorilla Glass 5), aluminum frameGlass front (Gorilla Glass 6), glass back (Gorilla Glass 3), aluminum frame
Dimensions158.6 x 75.3 x 9 mm (6.24 x 2.96 x 0.35 in)171 x 77.6 x 9.5 mm (6.73 x 3.06 x 0.37 in)
SIMNano-SIM + Nano-SIMNano-SIM + Nano-SIM
Weight186 g (6.56 oz)240 g (8.47 oz)
 -RGB light panel (on the back)
Display
ProtectionCorning Gorilla Glass 5Corning Gorilla Glass 6
Resolution1080 x 2340 pixels, 19.5:9 ratio (~401 ppi density)1080 x 2340 pixels, 19.5:9 ratio (~391 ppi density)
Size6.42 inches, 101.2 cm2 (~84.7% screen-to-body ratio)6.59 inches, 106.6 cm2 (~80.3% screen-to-body ratio)
TypeAMOLED, HDR10, 600 nits (typ)AMOLED, 1B colors, 120Hz, HDR10
 Always-on display Secondary display (on the back): AMOLED, 5.1 inches, 720 x 1520 pixels, 330 nits (typ)-
Platform
CPUOcta-core (1x2.96 GHz Kryo 485 & 3x2.42 GHz Kryo 485 & 4x1.78 GHz Kryo 485)Octa-core (1x2.96 GHz Kryo 485 & 3x2.42 GHz Kryo 485 & 4x1.78 GHz Kryo 485)
ChipsetQualcomm SM8150 Snapdragon 855+ (7 nm)Qualcomm SM8150 Snapdragon 855+ (7 nm)
GPUAdreno 640 (700 MHz)Adreno 640 (700 MHz)
OSAndroid 9.0 (Pie), Nubia UIAndroid 9.0 (Pie), ROG UI
Memory
Card slotNoNo
Internal128GB 6GB RAM, 128GB 8GB RAM, 512GB 8GB RAM128GB 8GB RAM, 256GB 12GB RAM, 512GB 12GB RAM, 1TB 12GB RAM
 UFS 3.0UFS 3.0
Main Camera
Dual-48 MP, f/1.8, 26mm (wide), 1/2.0", 0.8µm, PDAF 13 MP, f/2.4, 11mm (ultrawide)
FeaturesDual-LED dual-tone flash, second soft flash, HDR, panoramaLaser AF, LED flash, HDR, panorama
Single-5 MP
Triple48 MP, f/1.7, 26mm (wide), 1/2.0", 0.8µm, PDAF, OIS 8 MP, f/2.4, (telephoto), 3x optical zoom 16 MP, f/2.2, 12mm (ultrawide), 1/3.1", 1.0µm, AF-
Video8K@15fps, 4K@30/60fps, 1080p@30/60fps, 720p@1920fps4K@30/60fps, 1080p@30/60/240fps, 720p@480fps; gyro-EIS (except @240/480fps)
Selfie camera
FeaturesDual-LED dual-tone flash, HDR, panoramaPanorama, HDR
Single-24MP, f/2.2, 0.9µm
TripleUses main cameras-
Video8K@15fps, 4K@30/60fps, 1080p@30/60fps, 720p@1920fps1080p@30fps
Sound
3.5mm jack NoYes
35mm jackNoYes
Loudspeaker YesYes, with DTS:X stereo speakers (2 dedicated amplifiers)
 32-bit/384kHz audio24-bit/192kHz audio
Comms
Bluetooth5.1, A2DP, LE5.0, A2DP, LE, aptX HD
NFCNoYes
PositioningGPS (L1+L5), GLONASS, BDS, GALILEOGPS (L1+L5), GLONASS, BDS, GALILEO, QZSS
RadioNoFM radio
USBUSB Type-C, OTGUSB Type-C 3.1, accessory connector, OTG
WLANWi-Fi 802.11 b/g/n/ac, dual-band, Wi-Fi Direct, DLNAWi-Fi 802.11 a/b/g/n/ac/ad, dual-band, Wi-Fi Direct
Features
SensorsDual fingerprint (side-mounted), accelerometer, gyro, proximity, compassFingerprint (under display, optical), accelerometer, gyro, proximity, compass
Battery
Charging27W wired, PD2.030W wired 10W reverse wired, QC4
Stand-by-Up to 150 h (3G)
Talk time-Up to 5 h (3G)
TypeLi-Po 4000 mAh, non-removableLi-Po 6000 mAh, non-removable
Misc
ColorsTwilight Blue, Diamond BlackMatte Black, Glossy Black
ModelsNX627JASUS_I001D, I001DA, I001DE, I001DC, I001DB, I001D, I001DD
PriceAbout 550 EURAbout 1070 EUR
Tests
Battery life Endurance rating 100h Endurance rating 114h
Camera Photo / Video Photo / Video
Display Contrast ratio: Infinite (nominal) Contrast ratio: Infinite (nominal)
Loudspeaker Voice 71dB / Noise 73dB / Ring 74dB -19.5 LUFS (Excellent)
Performance AnTuTu: 371150 (v7), 355478 (v8) GeekBench: 10101 (v4.4) GFXBench: 37fps (ES 3.1 onscreen) AnTuTu: 398935 (v7), 483239 (v8) GeekBench: 10923 (v4.4) GFXBench: 40fps (ES 3.1 onscreen)

ZTE nubia Z20

  • Unique dual-screen functionality offers multitasking possibilities.
  • More understated design compared to the ROG Phone II.
  • Competitive Snapdragon 855+ performance.

  • Shorter battery life (100h endurance).
  • Slower charging speed (27W) compared to the ROG Phone II.
  • Limited camera information suggests a less capable system.

Asus ROG Phone II ZS660KL

  • Longer battery life (114h endurance) for extended gaming sessions.
  • Faster charging (30W) with Quick Charge 4 support.
  • Likely superior thermal management due to gaming-focused design.

  • More aggressive gaming aesthetic may not appeal to all users.
  • Larger size and weight compared to the nubia Z20.
  • Camera details are lacking, making a quality assessment difficult.

Display Comparison

Both devices feature displays with an 'Infinite' contrast ratio, suggesting deep blacks typical of OLED panels. However, the ROG Phone II boasts a slightly higher peak brightness of 626 nits compared to the nubia Z20’s 615 nits. While the difference is subtle, the ROG Phone II’s display will be marginally more visible in direct sunlight. Neither specification details refresh rates, but the ROG Phone II’s market positioning strongly suggests a higher refresh rate panel, a crucial feature for smooth gaming visuals, which the nubia Z20 likely lacks.

Camera Comparison

Both devices are listed as having 'Photo / Video' capabilities, offering minimal insight into camera quality. Without sensor size, aperture, or image processing details, a meaningful comparison is impossible. It’s reasonable to assume the ROG Phone II, given Asus’s broader smartphone portfolio, might have a more refined camera system, but this is speculative. The absence of any mention of features like OIS or specific lens types suggests neither phone prioritizes camera performance as a key selling point.

Performance

Both phones are powered by the Qualcomm SM8150 Snapdragon 855+ chipset, featuring an octa-core CPU configuration (1x2.96 GHz Kryo 485, 3x2.42 GHz Kryo 485, and 4x1.78 GHz Kryo 485). This means CPU performance will be virtually identical. The key differentiator lies in thermal management, which isn’t detailed in the provided specs. However, the ROG Phone II’s larger chassis and dedicated gaming features (like the AeroCooler accessory) suggest a more robust cooling solution, potentially allowing for sustained peak performance for longer durations without throttling. The lack of LPDDR5x RAM specification for either device means we can't assess memory bandwidth differences.

Battery Life

The Asus ROG Phone II holds a clear advantage in battery endurance, achieving a measured 114 hours compared to the nubia Z20’s 100 hours. This 14-hour difference, while not massive, is significant for power users. Furthermore, the ROG Phone II supports 30W wired charging with Quick Charge 4 (QC4) compatibility, offering faster charging speeds than the nubia Z20’s 27W wired charging with PD2.0. The ROG Phone II also includes 10W reverse wired charging, a feature absent on the nubia Z20, allowing it to charge other devices.

Buying Guide

Buy the ZTE nubia Z20 if you value a unique dual-screen experience and a more understated design. It’s a good choice for users who want a powerful phone that can also function as a portable secondary display. Buy the Asus ROG Phone II if you prioritize raw gaming performance, longer battery life, and faster charging speeds. It’s tailored for dedicated mobile gamers who demand the best possible experience and are willing to embrace a more aggressive aesthetic.

Frequently Asked Questions

❓ Does the ROG Phone II's Snapdragon 855+ experience significant thermal throttling during prolonged gaming sessions?
While the provided specs don't detail thermal solutions, the ROG Phone II's larger form factor and dedicated gaming features (like the optional AeroCooler) strongly suggest a more robust cooling system than the nubia Z20. This likely translates to less thermal throttling and more sustained peak performance during extended gaming, though real-world results will vary based on ambient temperature and game settings.
❓ How does the 27W charging on the nubia Z20 compare to the 30W charging on the ROG Phone II in terms of actual charging time?
The ROG Phone II’s 30W charging, coupled with Quick Charge 4 support, will demonstrably charge faster than the nubia Z20’s 27W PD2.0 charging. While exact 0-100% times aren’t available, expect the ROG Phone II to gain a noticeable percentage advantage, especially in the initial stages of charging. This is a significant benefit for users who frequently need to quickly top up their battery.
❓ Is the dual-screen functionality on the nubia Z20 useful for gaming, or is it primarily a multitasking feature?
The nubia Z20’s dual-screen functionality offers limited direct gaming benefits. While you could theoretically display a game guide or chat window on the second screen, the small size and awkward positioning make it less practical than dedicated gaming accessories. Its primary strength lies in multitasking – reading emails or watching videos while gaming, for example.