Dimensions
Size comparison
C28C4
| C28 | C4 | Difference | |
|---|---|---|---|
| Case size | 46.1 mm | 51 mm | −4.9 mm |
| Thickness | 13.3 mm | 9.8 mm | +3.5 mm |
| Weight | 44 g | 45 g | −0 g |
Drawn to the same scale from the official dimensions (front and side).
Why is C28 better than C4?
- Battery capacity410 mAh vs 300 mAh+37%
- Resolution (width)320 px vs 296 px+8%
Why is C4 better than C28?
- Water resistance1 ATM vs 2 ATM2×
- Thickness13.3 mm vs 9.8 mm+36%
Specifications
Side by side
| Design & durability | ||
| Case size | 58 mm | 51 mm |
| Weight | 44.5 g | 45 g |
| Thickness | 13.3 mm | 9.8 mm |
| Height | 58.3 mm | — |
| Width | 46.1 mm | — |
| Water resistance | 1 ATM | 2 ATM |
| Colours | Black, Green | — |
| Display | ||
| Screen size | 2.02″ | 2.01″ |
| Display technology | LCD | — |
| Panel | TFT LCD | — |
| AMOLED / OLED display | No | — |
| Resolution (width) | 320 px | 296 px |
| Resolution (height) | 390 px | 240 px |
| Pixel density | 250 ppi | — |
| Refresh rate | 60 Hz | — |
| Battery | ||
| Battery life (smartwatch mode) | — | 10 days |
| Battery capacity | 410 mAh | 300 mAh |
| Health sensors | ||
| Optical heart rate | Yes | Yes |
| Blood oxygen (SpO2) | Yes | Yes |
| Sleep tracking | — | Yes |
| Sensors | Accelerometer, heart rate, SpO2, blood pressure | — |
| Sports & navigation | ||
| Built-in GPS | No | — |
| Connectivity | ||
| NFC payments | No | — |
| LTE (cellular) | No | — |
| eSIM | No | — |
| Smart features | ||
| Calls from the wrist | — | Yes |
| Speaker | Yes | — |
| Platform | ||
| Operating system | Proprietary OS | — |
| Platform | Proprietary | — |
| Works with | — | Android, iOS |
