All Features

Bluetooth Proximity Tethering

Customizable distance zones with real-time RSSI measurement — both bracelet and phone vibrate when the child wanders too far.

4 ZonesSafe → Lost
In Simple Terms

"If you walk too far from your parents, both your bracelet and their phone buzz to say 'come back!' It's like an invisible leash made of radio waves — you can't see it, but it keeps you safe."

How It Works

The bracelet continuously measures RSSI (Received Signal Strength Indicator) between itself and the guardian's phone via Bluetooth 5.0 LE. RSSI values are converted to approximate distance using a calibrated path-loss model.

Four configurable zones: Safe (0-15ft, green), Near (15-30ft, yellow), Far (30-60ft, orange), Lost (60ft+, red). Each zone can trigger different alert behaviors — vibration, sound, or silent notification.

The 'who left who' algorithm determines whether the child walked away from the guardian or the guardian walked away from the child, based on motion sensor data from both devices.

In crowded environments, the system uses signal fingerprinting to maintain lock on the correct device even when surrounded by other Bluetooth sources.

Technical Specifications
ProtocolBluetooth 5.0 LE
Safe Zone0-15ft (configurable)
Near Zone15-30ft (configurable)
Far Zone30-60ft (configurable)
Lost Zone60ft+ (configurable)
RSSI Accuracy±3ft indoors, ±6ft outdoors
Update Rate4Hz (every 250ms)
Who Left WhoDual-device motion analysis
Crowd FilteringSignal fingerprinting
Power Draw8mA (active tethering)
Interactive Demo
Bluetooth 5.0 Tethering

Proximity Tethering — Always Connected

SafeStep maintains a constant encrypted Bluetooth link between the bracelet and your phone. The moment your child moves too far, you both know instantly — no cellular service required.

SAFE ZONEWARNING ZONEALERT ZONE15 ft30 ft50 ftGUARDIANCHILD

Distance

8 ft

Signal

Zone

Safe Zone

0 ft15 ft30 ft50 ft

Safe Zone

0–15 ft

Child is within safe range. Bracelet shows steady green pulse. No alerts.

Band

Steady green LED pulse every 5 seconds

Phone

Silent — green status indicator in app

Smartwatch

Green complication dot on watch face

All Zones

Signal Strength84%
BLE 5.0 · AES-128 encrypted · 2s ping interval

How Bluetooth Tethering Works

STEP 1

Pair & Calibrate

Guardian scans fingerprint on bracelet to establish encrypted BLE 5.0 bond. Signal baseline calibrated.

STEP 2

Continuous Ping

Band and phone exchange encrypted pings every 2 seconds. RSSI measured to estimate distance.

STEP 3

Zone Detection

Distance mapped to Safe / Warning / Alert zones. Thresholds adjustable in app (5–50 ft).

STEP 4

Instant Response

Zone change triggers immediate response: LED color shift, haptic feedback, and phone notification — all within 200ms.

Tethering Specifications

Protocol

BLE 5.0

Low energy, long range

Encryption

AES-128

End-to-end encrypted

Ping Rate

Every 2s

Adjustable 1–5 seconds

Range

Up to 300 ft

Open air, line of sight

Latency

< 200ms

Alert trigger to notification

Battery Impact

< 3%/day

Optimized duty cycling

Zones

3 configurable

Safe / Warning / Alert

No Subscription

Free forever

No cell service needed

Ready to protect your child?