| Basic Info | 
| Wear Type | Wristband | Wristband |  | 
| Price |  |  |  | 
| Ratings |  |  |  | 
| Activity & Fitness | 
| Activity | Yes | Yes | Both track daily activity | 
| Calories | Yes | Yes | Both show estimated calories burned | 
| Sleep | Yes | Yes | Both track sleep pattern | 
| Heart Rate / Pulse | Yes | Yes | Both have heart rate tracking | 
| Distance | Yes | Yes | Both track your stride length | 
| Steps | Yes | Yes | Both track how many steps you take | 
| Pace | Yes | No |  | 
| Speed | Yes | No |  | 
| Stairs / Floors | No | No | Both don't track climbing stairs or floors | 
| Exercise Tagging | Yes | No | Only Huawei Honor Band 3 provides exercise tagging | 
| Smart Coach | No | No | Both don't have coaching feature | 
| Goal Setting | No | No | Both don't have goal setting | 
| Inactivity Alert | No | Yes | Polaroid B521 helps you stay active with inactivity alert | 
| Additional Features | 
| GPS | No | No | Both don't have built-in GPS support | 
| Compass | No | No | Both don't have a compass | 
| Watch / Clock | Yes | Yes | Both have watch | 
| Alarm Clock | Yes | Yes | Both have alarm clock | 
| Reminders | Yes | Yes | Both have reminder app | 
| Stopwatch | Yes | Yes | Both have stopwatch | 
| Music Playback | No | No | Both don't have music playback | 
| Reports | Activity, Sleep | Activity, Sleep |  | 
| Smartphone Remote Features | 
| Notifications | Yes | Yes | Both show smartphone notifications | 
| Caller ID | Yes | Yes | Both show caller ID notification | 
| Music Control | Yes | Yes | Both allow control smartphone music player | 
| Call Control | Yes | No | Huawei Honor Band 3 allows you control phone calls | 
| Camera Control | No | Yes | Polaroid B521 has a smartphone's remote control function | 
| Find Phone | No | No | Both don't have a find phone feature | 
| Battery | 
| Duration | 30 days | n/a |  | 
| Battery Type | Rechargeable Battery | Rechargeable Battery |  | 
| Physical Specs | 
| Weather Resistance | Yes | Yes |  | 
| Waterproof | Yes | No |  | 
| IP Rating | 5 ATM | n/a |  | 
| Weight | 18 grams | n/a |  | 
| User Interface | 
| Display | OLED Screen | OLED Screen |  | 
| Display Size | 0.91 inches | 0,91 inches |  | 
| Screen Resolution | 128 x 32 pixels | 128*32 pixels |  | 
| Color Display | No | No |  | 
| Touch Screen | No | No |  | 
| Compatibility | 
| Android | Yes | Yes | Both compatible with Android devices | 
| iOS | Yes | Yes | Both compatible iOS devices | 
| OS X/Mac | No | No | Both don't compatible MAC OS X devices | 
| Windows Phone | No | No | Both don't compatible with Windows Phone devices | 
| Windows | No | No | Both don't have a find phone feature | 
| Web Portal | No | No | Both don't have online web portal option | 
| Social Features | No | No | Both don't have social features | 
| Connectivity | 
| Bluetooth | Yes | Yes | Both have Bluetooth data transfer technology | 
| Wi-Fi | No | No | Both don't have Wi-Fi connection | 
| NFC | No | No | Both don't have NFC connectivity | 
| ANT+ | No | No | Both don't provide ANT+ wireless technology | 
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