Polar M400 vs. Sony SmartBand 2 vs. ASUS ZenWatch 3 vs. Xiaomi Mi Band 4
 | | | | |
| PolarM400Remove Buy Now | SonySmartBand 2Remove Buy Now | ASUSZenWatch 3Remove Buy Now | XiaomiMi Band 4Remove Buy Now |
Basic Info | ||||
| Suggested Price | $200 | $130 | $229 | $25 |
| Release | 2014 | 2015 | 2017 | 2019 |
Activity & Fitness | ||||
| Calories | ||||
| Cycling (Bicycling) | ||||
| Distance | ||||
| Heart | n/a | |||
| Oxygen | ||||
| Sleep | ||||
| Steps | ||||
| Swim | ||||
Battery | ||||
| Duration | 8 hours to 30 days | 2 days | 48 hours | 20 days |
| Rechargeable | ||||
Compatibility | ||||
| Android | ||||
| iOS | ||||
| Windows Phone | n/a | n/a | ||
| Mac | n/a | |||
| Windows | n/a | |||
Connectivity | ||||
| Bluetooth | Yes | |||
| Cellular | ||||
| GPS | ||||
| NFC | ||||
| Wi-Fi | ||||
Display | ||||
| Color | n/a | |||
| Resolution | n/a | n/a | 400 x 400 | 120x240 |
| Size | n/a | n/a | 1.39 inches | 0.95 inches |
| Touch | n/a | |||
| Type | n/a | n/a | AMOLED | AMOLED |
Functions | ||||
| Audio Speaker | Alerts only | |||
| Clock | ||||
| Phone | ||||
| Vibration | ||||
| Voice | ||||
Hardware | ||||
| Accelerometer | ||||
| Barometer or Altimeter | ||||
| Ultraviolet Sensor | ||||
| Water Resistance | 3 ATM | IP58 | 5 ATM | |
Notifications | ||||
| Phone | ||||
| Emails | ||||
| Texts | ||||
Software | ||||
| Operating System | n/a | n/a | Android Wear 2 | AMAZFIT OS |
| Apps | ||||
| Music | ||||