IoT Smart Watch Development with BLE & Mobile App Integration

Our customer is an innovative product developer specializing in health and fitness technologies, including next generation wearables such as smartwatches and related solutions. The client operates from its corporate headquarters in Philadelphia, Pennsylvania, USA, and manages manufacturing operations in China, enabling large scale production and global distribution of its devices.

Our client approached Adequate Infosoft with the goal of designing a state of the art smartwatch based on Nordic Semiconductor’s nRF52 Series platform. The device was planned to include advanced health monitoring, comprehensive workout tracking, and the latest performance metrics related to jump analysis, including jump height and jump velocity. This engagement was intended to serve as the foundation for a long term engineering collaboration.

The primary goals of the project were

• Design a production ready smart wrist watch using Nordic nRF52832/nRF52840
• Develop a low power optimized RTOS based firmware
• Use sensor fusion to measure accurately both Jump Velocity / Jump Height
• Track Activities of Daily Living as well as Health/CrossFit
• Deliver fully functional prototypes to a production facility for mass production
• Provide a design that can be scaled up, scaled out and certified

1. Accurate Jump Analytics

Unlike basic fitness trackers, the smartwatch needed to precisely calculate jump velocity and jump height, which requires:

• High-frequency sensor sampling
• Accurate time synchronization
• Advanced motion analysis algorithms
• Noise filtering and calibration

2. Power Efficiency

As a wearable device, battery life was critical. The challenge was to balance:

• Continuous sensor data collection
• BLE communication
• RTOS task scheduling
• Low-power sleep modes

3. Manufacturing Readiness

The client required stable prototypes that had completed testing and were ready to be sent directly to the factory in China for mass production, without the need for additional redesign cycles.

Adequate Infosoft provided a complete end-to-end solution , from start to finish that included everything from the analysis and design phase through to the final production release stage (i.e., hardware, firmware, algorithm development/testing, and transfer of ownership).

Hardware Design & Development

Nordic Platform Selection

We made our choice based on performance/power specs by using the following microcontroller(s):

• nRF52840 (advanced versions), nRF52832 (cost-optimized production) for best-in-class BLE performance, ultra-low power consumption, strong ecosystem support.

Both controllers offered:

• Excellent BLE performance
• Ultra-low power consumption
• Strong ecosystem support

Hardware Components

• 6-axis IMU (accelerometer + gyroscope)
• Heart rate sensor
• High efficiency PMIC and battery charging circuit
• OLED display interface
• BLE antenna optimized for wearable form factor

PCB & RF Design

• Multi-layer PCB designed to be RF optimized
• Antenna tuning for consistent BLE signal
• Separation of power domains to reduce noise
• Design for compactness so that it can be worn on the wrist

Firmware & RTOS Development

RTOS Architecture

We implemented an RTOS-based firmware architecture using Nordic’s SDK, ensuring:

• Modular task separation
• Predictable real-time performance
• Efficient power management

Firmware Features

• Sensor drivers with high-frequency sampling
• BLE GATT services for data synchronization
• Secure device pairing and bonding
• Power state management (active, idle, deep sleep)
• OTA-ready firmware structure

This was the core innovation of the project.

Approach

• High-speed accelerometer data acquisition
• Sensor fusion and calibration
• Gravity compensation
• Peak detection and time-of-flight calculation
• Noise filtering using digital filters

Outcome

The algorithm delivered:

• Accurate jump height measurement
• Consistent jump velocity tracking
• Repeatable results across multiple workout sessions

The solution was validated through controlled test scenarios and real-user trials.

In addition to jump analytics, the smartwatch supported:

• Heart rate monitoring
• Step counting
• Workout session tracking
• Activity duration and intensity analysis

All data was structured for:

• On-device visualization
• BLE synchronization with companion apps

Prototype Development

We delivered:

• Fully assembled smartwatch prototypes
• Production-grade PCB revisions
• Enclosure-ready electronics

Testing Process

• Functional validation
• Power consumption profiling
• BLE connectivity testing
• Long-duration stability tests
• Sensor accuracy validation

Issues identified during testing were resolved before factory handover.

To support smooth mass production, Adequate Infosoft provided:

• Complete hardware documentation
• Firmware binaries and versioned source code
• Programming and flashing procedures
• Test guidelines for factory QA
• DFM recommendations

The prototypes were successfully transferred to the China-based factory, and the product is now entering the manufacturing phase.

• Functional wearable smart watch prototype has been delivered and tested
• Accurate measuring of jump velocity and height has been achieved
• Low power usage indicates that it will be usable for daily wear
• Manufacturing-ready design has been developed with minimal risk
• Strong foundation for long-term product roadmap

As well as being happy with the technology, the customer was also very pleased with how Adequate Infosoft communicated openly and effectively during the project, held themselves accountable, and were able to get things done on schedule.

As a result of this successful project, Adequate Infosoft is currently engaged with the customer in discussions regarding:

• Additional functionality
• Mobile applications
• Analytical support through cloud services
• Additional variations on future wearables.

This project marked the beginning of a long-term collaboration between Adequate Infosoft and the client.

This case study highlights the extensive experience Adequate Infosoft has gained through years of working with Nordic’s nRF52 platforms, including hardware engineering, firmware development using real time operating systems, motion algorithms, and manufacturing for production ready products.

By taking the concept through to fully manufacture ready prototypes, Adequate Infosoft delivered a complete smartwatch solution. Rather than producing a simple demo, we positioned the client for successful mass production and a confident product launch in the marketplace.