In depth comparison and review of CAT S31 and Realme C21. Compare sizes, cameras, batteries, memory, and other important specifications and features to easily choose the right phone for you. Our goal is to help you uncover differences between the products and find the phone that will best fit your needs.
| DESIGN AND DIMENSIONS | CAT S31 | Realme C21 |
|---|
| Product Type | Smartphone | Smartphone | |
|---|---|---|---|
| Form Factor | Touch - Rugged | Touch | |
| Height | 146 mm | 165.2 mm | Realme C21 has greater height than CAT S31. |
| Width | 74.42 mm | 76.4 mm | Realme C21 has greater width than CAT S31. |
| Depth | 12.6 mm | 8.9 mm | Realme C21 is narrower than CAT S31. |
| Weight | 200 g | 190 g | Realme C21 is lighter than CAT S31. |
| Body Colour | - | Cross black | Cross blue | |
| Protection | Shockproof, dustproof, waterproof | - | |
| Waterproof (Water-resistant) | Yes | - | CAT S31 is waterproof. |
| IP rating | IP68 | - | |
| SAR Value | 1.649 W/kg (body), 0.799 W/kg (head) | - | |
| Connector Type | Micro-USB - 5 pin Micro-USB Type B Headset jack - mini-phone 3.5mm |
Micro-USB Headset jack - mini-phone 3.5mm |
|
| SIM Card Type (Size) | Nano SIM | Nano SIM | |
| SIM Card Qty | Dual-SIM | Dual-SIM |
| DISPLAY | CAT S31 | Realme C21 |
|---|
| Display Type | LCD display | LCD display | |
|---|---|---|---|
| Display Technology | IPS | LCD | |
| Screen Size (Display Size) | 4.7" | 6.5" | Realme C21 has larger screen size than CAT S31. |
| Screen Resolution (Display Resolution) | 1280 x 720 pixels | 1600 x 720 pixels | Realme C21 has better screen resolution than CAT S31. |
| Display Format | HD | HD+ | |
| Aspect Ratio | - | 20:9 | |
| Max Brightness | - | 420 cd/m² | |
| Display Enhancement Technology | Super Bright Display | - | |
| Display Features | - | Mini-drop display | |
| Display Protection (Screen Protector) | Corning Gorilla Glass 3 (scratch resistant glass) | - |
| PROCESSOR | CAT S31 | Realme C21 |
|---|
| Processor Type (CPU) | Qualcomm | MediaTek Helio G35 | |
|---|---|---|---|
| Processor Number | MSM8909 | - | |
| Clock Speed | - | 2.3 GHz | |
| Processor Core Qty | Quad-core | 8-core | Realme C21 has higher processor core quantity than CAT S31. |
| Graphics System (GPU) | - | PowerVR GE8320 |
| MEMORY | CAT S31 | Realme C21 |
|---|
| RAM | 2 GB | LPDDR4X SDRAM - 3 GB | Realme C21 has more RAM than CAT S31. |
|---|---|---|---|
| Internal Memory Size (Storage Capacity) | 16 GB | 32 GB | Realme C21 has more internal memory than CAT S31. |
| Supported Flash Memory Cards (Expandable Memory) | microSDHC, microSDXC - up to 128 GB | microSD |
| CAMERA | CAT S31 | Realme C21 |
|---|
| MAIN CAMERA |
|---|
| Number of Main Cameras | 1 | 3 | |
|---|---|---|---|
| Sensor Resolution | 8 Megapixel | 13 Megapixel | Realme C21 has better camera resolution than CAT S31. |
| Lens Aperture | - | F/2.2 | |
| Lens Construction | - | 5-element | |
| Focus Adjustment | Automatic | Automatic | |
| Digital Zoom | - | 4x | |
| Special Effects | - | HDR | |
| Camera Modes | - | Panorama, Time-lapse mode, Slow motion mode, Beauty mode, Expert Mode, Nightscape capture mode, Portrait, Filter mode, Super nightscape | |
| Light Source | LED flash | LED flash | |
| Video Resolutions | 1280 x 720 (720p) at 120 fps | 1920 x 1080 (1080p) at 30 fps | |
| Camera Features (Functions) | - | Phase Detect Auto-Focus (PDAF), AI Triple camera, Chroma boost |
| SECOND CAMERA |
|---|
| Sensor Resolution (2nd Camera) | - | 2 Megapixel | |
|---|---|---|---|
| Lens Aperture (2nd Camera) | - | F/2.4 | |
| Lens Element Qty (2nd Camera) | - | 3-element | |
| Camera Functions (2nd Camera) | - | B&W lens |
| THIRD CAMERA |
|---|
| Sensor Resolution (3rd Camera) | - | 2 Megapixel | |
|---|---|---|---|
| Lens Aperture (3rd Camera) | - | F/2.4 | |
| Lens Element Qty (3rd Camera) | - | 3-element | |
| Camera Functions (3rd Camera) | - | Macro camera | |
| Camera Features (3rd Camera) | - | 4cm macro photography |
| FRONT CAMERA |
|---|
| Number of Front Cameras | 1 | 1 | |
|---|---|---|---|
| Sensor Resolution (Front) | 2 Megapixel | 5 Megapixel | Realme C21 has better front camera resolution than CAT S31. |
| Lens Aperture (Front) | - | F/2.2 | |
| Lens Element Qty (Front) | - | 3-element | |
| Focus Adjustment | Focus free | - | |
| Special Effects (Front) | - | HDR | |
| Camera Modes (Front) | - | Time-lapse mode, Beauty mode, portrait mode, AI Beauty, Filter mode, Panoramic mode | |
| Face Recognition (Face ID) | - | Face recognition | Realme C21 has face detection. |
| BATTERY AND CHARGING | CAT S31 | Realme C21 |
|---|
| Battery Capacity (Battery Size) | 4000 mAh | 5000 mAh | Realme C21 has larger battery capacity than CAT S31. |
|---|---|---|---|
| Standby Time | 912 hours | - | |
| Talk Time | 1800 minutes | - | |
| Run Time Details | Talk: up to 1800 min Standby: up to 912 hrs |
- | |
| Battery Technology | Lithium Ion | - |
| CELLULAR | CAT S31 | Realme C21 |
|---|
| Technology | WCDMA (UMTS) / GSM | WCDMA (UMTS) / GSM | |
|---|---|---|---|
| Mobile Broadband Generation | 4G | 4G | Both phones have the same mobile network generation. |
| Operating System | Android 7.0 Nougat | Android 10 | |
| User Interface | - | Realme UI | |
| Navigation | GPS, A-GPS, GLONASS, BeiDou | GPS, A-GPS, GLONASS, BeiDou |
| COMMUNICATIONS | CAT S31 | Realme C21 |
|---|
| Data Transmission | GPRS, EDGE, HSDPA, HSUPA, HSPA+, LTE | FDD-LTE, TDD-LTE | |
|---|---|---|---|
| 2G Band | 850 GSM, 900 GSM, 1800 GSM, 1900 GSM | 850 GSM, 900 GSM, 1800 GSM, 1900 GSM | |
| 3G UMTS Band | Band 1, Band 2, Band 5, Band 8 | Band 1, Band 5, Band 8 | |
| 3G UMTS Frequency | 2100, 1900, 850, 900 | 2100, 850, 900 | |
| 4G LTE Band | Band 1, Band 2, Band 3, Band 5, Band 7, Band 8, Band 20 | Band 1, Band 3, Band 5, Band 7, Band 8, Band 20, Band 28, Band 38, Band 40, Band 41 | |
| 4G LTE Frequency | FDD 2100, FDD 1900 PCS, FDD 1800+, FDD 850, FDD 2600, FDD 900, FDD 800 DD | FDD 2100, FDD 1800+, FDD 850, FDD 2600, FDD 900, FDD 800 DD, FDD 700 APT, TDD 2600, TDD 2300, TDD 2500 | |
| Wireless Interface | IEEE 802.11b/g/n | IEEE 802.11b/g/n | |
| Bluetooth | Bluetooth 4.1 | Bluetooth 5.0 | |
| Messaging Services | SMS, MMS | - |
| FEATURES | CAT S31 | Realme C21 |
|---|
| Phone Functions | Speakerphone, voice control, call timer, conference call, flight mode, voice dialing, vibrating alert | Speakerphone, voice control, call timer, conference call, flight mode, voice dialing, vibrating alert | |
|---|---|---|---|
| Sensors | Accelerometer, ambient light sensor, proximity sensor, digital compass | Accelerometer, proximity sensor, magnetometer, light sensor | |
| Security Devices | - | Fingerprint reader | |
| Additional Phone Features | Dual microphones, Wet Touchscreen Operation, Glove Touchscreen Operation | Super power saving mode, HyperEngine technology, Reverse charging | |
| Android Enterprise Recommended | Yes | - |
| OTHERS | CAT S31 | Realme C21 |
|---|
| Included Accessories | Power adapter | USB cable, power adapter, SIM card removal tool | |
|---|---|---|---|
| Compliant Standards | MIL-STD 810G, IP68 | TUV Rheinland | |
| Max Depth of Water Resistance | 1.2 m | - | |
| Max Height of Shock Resistance | 1.8 m | - | |
| Max Operating Temperature | 55 °C | - | |
| Min Operating Temperature | -30 °C | - |
cs
sk
de
it
es
fr
hu
pt
ru
pl
br
ro
