Vivo X21i vs Vivo X20
| Type | Touch | Touch |
| Dimensions | 154.37 x 74.98 x 6.99 mm | 155.85 x 75.15 x 7.20 mm |
| Weight | 159.00 g | 159.00 g |
| Display size | 6.28" | 6.01" |
| Display | Color / Super AMOLED 16M colors 1080 x 2280 px (6.28") 402 ppi | Color / Super AMOLED 16M colors 1080 x 2160 px (6.01") 402 ppi |
| Display protection |   | |
| Additional display | | |
| Protection of the secondary display | | |
| Standard battery | Li-Ion 3240 mAhBuy powerbank
| Li-Ion 3245 mAhBuy powerbank
|
| Quick battery charging | | |
| Wireless battery charging | | |
| Internal memory | 64 GB, 128 GB | 64 GB |
| RAM memory | 4 GB, 6 GB | 4 GB |
| Memory cards |  microSD, microSDHC, microSDXC up to 256 GBBuy memory card | microSD, microSDHC, microSDXC up to 256 GBBuy memory card |
| Operating system | Android 8.1 Oreo | Android 7.1.1 Nougat |
| Interface | Funtouch 4.0 | Funtouch 3.2 |
| Processor | MediaTek Helio P60 MT6771 | Qualcomm Snapdragon 660 |
| Processor clock | 2000 MHz | 2200 MHz |
| GPU | ARM Mali-G72 MP3 @800 MHz | Adreno 512 |
| Touchscreen | | |
| DualSIM | | |
| DualSIM mode | dual standby | dual standby |
| Hybrid DualSIM |  | |
| Announced | 2Q 2018 | 3Q 2017 |
| Other names | - | - |
| GSM frequencies | 850 900 1800 1900 | 850 900 1800 1900 |
| UMTS | 850 900 2100 | 850 900 1900 2100 |
| LTE standard | FDD LTE: 2100, 1800, 1700, 900, 850 TDD LTE: 2600, 2500, 2300, 1900 | FDD LTE: 2600, 2100, 1900, 1800, 900, 850 TDD LTE: 2600, 2500, 2300, 1900 |
| CDMA | 850 | 850 |
| Standard TD-SCDMA | 1900 2000 | 1900 2000 |
| UMA | | |
CAMERAS - BACK
| First camera | | |
| Photo matrix | 12 Mpx | 12 Mpx |
| Optical zoom | | |
| Flash | LED | LED |
| Dual-colour LED flash | | |
| Video formats | MPEG4, H.263, H.264 | MPEG4, H.263, H.264 |
| Additional | - | AF, f/1.8 |
| Second camera | | |
| Photo matrix | 5 Mpx | 5 Mpx |
| Resolution | | 2592x1944 px |
| Optical zoom | | |
| Flash | LED | |
| Dual-colour LED flash | | |
| Video formats | MPEG4, H.263, H.264 | MPEG4, H.263, H.264 |
| Additional | - | - |
CAMERAS - FRONT
| First camera | | |
| Photo matrix | 24 Mpx | 12 Mpx |
| Optical zoom | | |
| Flash | | |
| Dual-colour LED flash | | |
| Video formats | MPEG4, H.263, H.264 | MPEG4, H.263, H.264 |
| Additional | - | f/2.0 |
SENSORS
| Accelerometer | | |
| Proximity | | |
| Light | | |
| Magnetometer | | |
| Gyroscope | | |
| Barometer | | |
| Altimeter | | |
| Gravity | | |
| Hall-effect | | |
| Iris scanner | | |
| Fingerprint scanner | | |
| Thermometer | | |
| Hygrometer | | |
Data transfer
| xHTML | | |
| WAP | v2.0 | v2.0 |
| HSCSD | | |
| HSDPA | | |
| HSUPA | | |
| HSPA | | |
| HSPA+ | | |
| LTE DL | | |
| LTE UP | | |
| WIMAX+ | | |
| GPRS | | |
| EDGE | | |
| Bluetooth | | v5.0 |
| A2DP Profile | | |
| HDMI | | |
| WiFi | | v802.11 a/b/g/n/ac |
| WiFi frequencies | 2,4 GHz | 2,4 GHz; 5 GHz |
| DLNA | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v2.0 | v2.0 |
| GPS | | |
| A-GPS | | |
| Beidou | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | XT9 | XT9 |
| Swype | | |
| e-mail client | POP3, IMAP4, SMTP | POP3, IMAP4, SMTP |
| Hardware QWERTY keyboard | | |
| RSS Reader | | |
Multimedia
| Radio | | |
| MP3 | | |
| Stereo speakers | | |
| Audio Jack | 3.5 mm | 3.5 mm |
| HD Voice | | |
| Sound formats | AAC, AMR, APE, FLAC, OGG, WAV, WMA | AAC, AMR, APE, FLAC, OGG, WAV, WMA |
| Polyphony | | |
| Video ringtone | | |
| Ring composer | | |
| Java | ART | ART |
| Videophone | | |
| DVB-H television | | |
| TV-Out | | |
PIM AND ADDITIONAL FUNCTIONS
| Watch | | |
| Stopwatch | | |
| Alarm | | |
| Calculator | | |
| Currency converter | | |
| Organizer | | |
| Calendar | | |
| Flight mode | | |
| SyncML | | |
| Data and fax | | |
| Screensaver | | |
| Themes | | |
| Interchangeable covers | | |
| Voice dial | | |
| Speakerphone | | |
| Recorder | | |
| Vibrations | | |