Safe Radius was a 2015 UC Berkeley student prototype that paired a guardian’s phone with a child-worn Moto 360 watch. It was designed to let a guardian set a distance boundary, message the child, receive an out-of-range alert, and open a map-style locating screen. Its GPS-based locating and automatic movement detection were simulated or left unimplemented, so it should not be treated as a working or maintained child-tracking product.
What Safe Radius was designed to do
Team HYJJR developed Safe Radius for UC Berkeley’s Summer 2015 CS160 course. Hackster lists the project as published on August 4, 2015. The team described the problem as guardians and children becoming distracted while exploring, so the child may get lost. The proposed design aimed to offer the child some freedom while giving the guardian a way to stay connected.
The project’s core arrangement was a guardian’s phone paired over Bluetooth with a Moto 360 worn by the child. As the team put it, “This app solves this problem by connecting the child and guardian with the phone on guardian and the watch on child.” Team HYJJR’s Safe Radius project documentation on Hackster describes the design and prototype behavior.
How the phone and watch interaction was meant to work
Set up a boundary and contact the child
After connecting the phone and watch over Bluetooth, the guardian would use the phone app. Its main send page offered preset messages and a field for custom text. Tabs at the bottom led to the send, map, and settings screens. In settings, the guardian could enable or disable the feature, set the radius, and control the guardian image.
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- Real-Time GPS Tracking & Safe Zone Alerts: Attention: The Watch only supports US, not support other countries.Stay connected with your child through real-time location tracking on Google Maps. With AI-assisted positioning and multi-satellite GPS technology,such as GPS、GLONASS、Galileo、BeiDou、QZSS、NavIC satellite systems,this kids smart watch helps deliver more accurate location updates for everyday use. Parents can view location history, check daily routes, set multiple geofences, and receive instant alerts when kids enter or leave safe zones. You can also refresh the location anytime or remotely ring the watch to help find it quickly.
- 4G Video Call, Voice Call & Smart Communication: Stay connected with your child through 4G video calls, voice calls, instant messaging, and family group chat. Built with Multi-Band LTE, Wi-Fi Support, a High-Sensitivity Antenna, and SignalBooster technology, this kids smart watch helps provide a stronger and more stable connection via SIM card or WiFi. Kids can send voice messages, text, and emojis, make one-tap calls, or use the dial pad easily. With GPS + Wi-Fi + LBS Positioning, parents can also get more reliable location updates, making it a smart first phone alternative for kids.
- SOS Emergency Call & Remote Monitoring. In emergencies, kids can press and hold the SOS button to automatically call preset contacts. Parents can also use remote listening to hear the surrounding environment when needed. SMS alerts and app notifications ensure you’re always informed about your child’s safety.
- AI Smart Features, Camera & Entertainment. Built-in AI voice assistant, translation, and image recognition make learning fun and interactive. The watch also includes a camera, album, games, stopwatch, calculator, alarms, and sports modes. Kids can explore, learn, and stay entertained throughout the day.
- Advanced Parental Controls & Class Mode. Take full control through the app. Manage contacts, block unknown calls, disable dial pad, and set class mode to prevent distractions during school hours. Additional features include scheduled power on/off, remote shutdown/restart, call restrictions, and customizable settings for a safe digital environment.
Receive an alert and open the locating screen
The intended behavior was for the phone to notify the guardian when the child moved outside the defined radius. The map screen showed the guardian as a blue location point, surrounded by a black circle representing the radius, with a red point for the child. The interface was intended to help the guardian orient toward the child after separation.
Let the child acknowledge or reply
On the watch, a notification displayed the guardian’s image and message. The child could swipe to acknowledge it with a checkmark, then use an envelope screen to reply. The redesign simplified the watch notification and gave phone notifications clearer DISMISS and GO TO APP actions.
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- Real-Time GPS Tracking & Safe Zone Alerts: Attention: The Watch only supports US, not support other countries. Stay connected with your child through real-time location tracking on Google Maps. With AI-assisted positioning and multi-satellite GPS technology,such as GPS、GLONASS、Galileo、BeiDou、QZSS、NavIC satellite systems,this kids smart watch helps deliver more accurate location updates for everyday use. Parents can view location history, check daily routes, set multiple geofences, and receive instant alerts when kids enter or leave safe zones. You can also refresh the location anytime or remotely ring the watch to help find it quickly.
- 4G Video Call, Voice Call & Smart Communication: Stay connected with your child through 4G video calls, voice calls, instant messaging, and family group chat. Built with Multi-Band LTE, Wi-Fi Support, a High-Sensitivity Antenna, and SignalBooster technology, this kids smart watch helps provide a stronger and more stable connection via SIM card or WiFi. Kids can send voice messages, text, and emojis, make one-tap calls, or use the dial pad easily. With GPS + Wi-Fi + LBS Positioning, parents can also get more reliable location updates, making it a smart first phone alternative for kids.
- SOS Emergency Call & Remote Monitoring. In emergencies, kids can press and hold the SOS button to automatically call preset contacts. Parents can also use remote listening to hear the surrounding environment when needed. SMS alerts and app notifications ensure you’re always informed about your child’s safety.
- AI Smart Features, Camera & Entertainment. Built-in AI voice assistant, translation, and image recognition make learning fun and interactive. The watch also includes a camera, album, games, stopwatch, calculator, alarms, and sports modes. Kids can explore, learn, and stay entertained throughout the day.
- Advanced Parental Controls & Class Mode. Take full control through the app. Manage contacts, block unknown calls, disable dial pad, and set class mode to prevent distractions during school hours. Additional features include scheduled power on/off, remote shutdown/restart, call restrictions, and customizable settings for a safe digital environment.
What worked in the prototype—and what was simulated
The available project documentation describes interface behavior and design intent, not a validated tracking system. The prototype’s location and alert limitations matter if you are asking whether Safe Radius could reliably keep track of a child:
- No working GPS locating in this setup: The team said the Moto 360 used for the prototype did not provide GPS functionality. The map’s red child marker was an arbitrary point rather than a GPS-reported location.
- Out-of-radius movement was simulated: Because the watch could not generate the intended boundary-crossing event, a timer simulated the child moving farther away. The automatic movement alert was therefore not demonstrated as a real location-triggered alert.
- Some location details were only planned: The team intended to include distance and altitude text but did not implement it.
- Guardian-image upload was omitted: Although the interface included a guardian image, uploading one was not implemented.
The team also changed the design during iteration: it replaced a less intuitive radar display with a map, added feet as a distance unit, and moved infrequently used controls into settings. Those choices describe interface revisions; they do not establish location accuracy, alert reliability, or real-world safety performance.
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- Real-Time GPS Tracking & Safe Zone Alerts: Attention: The Watch only supports US, not support other countries.Stay connected with your child through real-time location tracking on Google Maps. With AI-assisted positioning and multi-satellite GPS technology,such as GPS、GLONASS、Galileo、BeiDou、QZSS、NavIC satellite systems,this kids smart watch helps deliver more accurate location updates for everyday use. Parents can view location history, check daily routes, set multiple geofences, and receive instant alerts when kids enter or leave safe zones. You can also refresh the location anytime or remotely ring the watch to help find it quickly.
- 4G Video Call, Voice Call & Smart Communication: Stay connected with your child through 4G video calls, voice calls, instant messaging, and family group chat. Built with Multi-Band LTE, Wi-Fi Support, a High-Sensitivity Antenna, and SignalBooster technology, this kids smart watch helps provide a stronger and more stable connection via SIM card or WiFi. Kids can send voice messages, text, and emojis, make one-tap calls, or use the dial pad easily. With GPS + Wi-Fi + LBS Positioning, parents can also get more reliable location updates, making it a smart first phone alternative for kids.
- SOS Emergency Call & Remote Monitoring. In emergencies, kids can press and hold the SOS button to automatically call preset contacts. Parents can also use remote listening to hear the surrounding environment when needed. SMS alerts and app notifications ensure you’re always informed about your child’s safety.
- AI Smart Features, Camera & Entertainment. Built-in AI voice assistant, translation, and image recognition make learning fun and interactive. The watch also includes a camera, album, games, stopwatch, calculator, alarms, and sports modes. Kids can explore, learn, and stay entertained throughout the day.
- Advanced Parental Controls & Class Mode. Take full control through the app. Manage contacts, block unknown calls, disable dial pad, and set class mode to prevent distractions during school hours. Additional features include scheduled power on/off, remote shutdown/restart, call restrictions, and customizable settings for a safe digital environment.
Can Safe Radius keep a child from getting lost?
No evidence in the project documentation establishes that it can do so. Safe Radius is best understood as a student interaction-design prototype that illustrates a phone-and-watch safety concept, not as a documented commercial service. The available materials report no measured performance results or user-study sample size. In particular, the simulated boundary event and arbitrary map marker mean the prototype does not show that it could detect a child leaving a real-world safe radius or locate that child afterward.
For anyone evaluating a current child-safety wearable, the useful questions raised by Safe Radius are whether the device has a working location source, how boundary alerts are generated and delivered, whether messaging works both ways, and how the child acknowledges or responds. The project itself does not establish answers about present-day products or the Moto 360’s current availability or compatibility.
Quick Recap
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- Easily Pair via Internal QR Code: Connecting this kids’ smart watch is effortless. Simply download the Junicare App and scan the built-in QR code on the watch with your phone to finish pairing in seconds. As a parent, you can flexibly manage your child’s watch contacts through the App, block unknown incoming calls, and check your kid’s real-time location anytime. It safeguards your child’s communication security at every step, saving you the trouble of complicated operations
- 4G Calling / Chatting / Video Chat: Insert the included 4G SIM card to enjoy smooth 4G voice calls, text chat and video calls. Equipped with a front-facing camera, the watch supports two-way HD video chat, allowing you to check on your child anytime even when you’re busy. The one-touch SOS emergency call feature adds extra protection: kids can contact parents instantly by pressing a single button during emergencies, bringing great peace of mind to your little ones
- Precise Location & Safety Geofence:No more constant supervision! This smart watch adopts dual GPS + LBS positioning technology to provide real-time location of your child. Customize exclusive electronic geofences on the App, such as safe areas around home and school. Once your child steps out of the designated range, your phone will get an instant alert, relieving your worries about their,Whereabouts.Supports 24-hour route playback, allowing you to view every place you’ve been at any time
- Class Mode & Daily Entertainment: Tailored perfectly for parents’ needs to prevent kids from distracting themselves with the watch during class. Parents can remotely activate Class Mode via the mobile App and set usable time limits. Unnecessary entertainment functions (games, calculator, pedometer, stopwatch) will be disabled, leaving only positioning and emergency calling available. This helps children stay focused on studying, balancing learning and daily use reasonably
- Comfortable & Stylish Perfect Gift Idea: Equipped with a 1.7-inch curved HD IPS screen, the watch delivers clear and soft visuals for comfortable viewing. It comes with a skin-friendly breathable silicone strap and a trendy woven strap, perfectly fitting kids’ delicate skin. Lightweight and comfy for all-day wear without burden. Featuring a unisex design with sleek looks, it is an ideal pick for daily use, birthday gifts, and holiday presents for both boys and girls
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- Easily Pair via Internal QR Code: Connecting this kids’ smart watch is effortless. Simply download the Junicare App and scan the built-in QR code on the watch with your phone to finish pairing in seconds. As a parent, you can flexibly manage your child’s watch contacts through the App, block unknown incoming calls, and check your kid’s real-time location anytime. It safeguards your child’s communication security at every step, saving you the trouble of complicated operations
- 4G Calling / Chatting / Video Chat: Insert the included 4G SIM card to enjoy smooth 4G voice calls, text chat and video calls. Equipped with a front-facing camera, the watch supports two-way HD video chat, allowing you to check on your child anytime even when you’re busy. The one-touch SOS emergency call feature adds extra protection: kids can contact parents instantly by pressing a single button during emergencies, bringing great peace of mind to your little ones
- Precise Location & Safety Geofence:No more constant supervision! This smart watch adopts dual GPS + LBS positioning technology to provide real-time location of your child. Customize exclusive electronic geofences on the App, such as safe areas around home and school. Once your child steps out of the designated range, your phone will get an instant alert, relieving your worries about their,Whereabouts.Supports 24-hour route playback, allowing you to view every place you’ve been at any time
- Class Mode & Daily Entertainment: Tailored perfectly for parents’ needs to prevent kids from distracting themselves with the watch during class. Parents can remotely activate Class Mode via the mobile App and set usable time limits. Unnecessary entertainment functions (games, calculator, pedometer, stopwatch) will be disabled, leaving only positioning and emergency calling available. This helps children stay focused on studying, balancing learning and daily use reasonably
- Comfortable & Stylish Perfect Gift Idea: Equipped with a 1.7-inch curved HD IPS screen, the watch delivers clear and soft visuals for comfortable viewing. It comes with a skin-friendly breathable silicone strap and a trendy woven strap, perfectly fitting kids’ delicate skin. Lightweight and comfy for all-day wear without burden. Featuring a unisex design with sleek looks, it is an ideal pick for daily use, birthday gifts, and holiday presents for both boys and girls
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