Safety Band & App Coding

@Microlent

Hello, I understand that you are looking for a freelancer to develop both the embedded firmware for your wearable safety band and the companion mobile application for health monitoring purposes. My expertise lies in full-stack solutions, encompassing both hardware and software development. After carefully reviewing your project requirements, I am confident in my ability to deliver a reliable solution. For the firmware, I will efficiently read the heart-rate sensor, implement data filtering, manage power consumption effectively, and ensure seamless Bluetooth Low Energy communication. On the software side, I will create a user-friendly companion app that offers real-time and historical heart-rate graphs, local data storage, cloud synchronization, and push alerts for abnormal readings. With experience in developing native iOS and Android apps using Swift, Kotlin, and cross-platform frameworks like Flutter and React Native, I am well-equipped to meet your needs. By focusing on heart-rate accuracy, BLE stability, and App Store compliance, I will ensure a high-quality end product. You can view examples of my previous work in my portfolio: https://www.freelancer.com/u/Microlent If my approach aligns with your vision, I am eager to discuss the project further. Let's chat to explore how we can transform your prototype into a polished, production-ready solution. Sincerely, Rajesh

@DrSyafiq

This is a strong fit, and I’d start with the highest-risk workflow first. For a Safety Band & App Coding, the hard part is balancing sensor scanning accuracy, battery life, Bluetooth/SIM fallback, and OTA-ready embedded reliability. My approach would be to validate the sensor matrix and power budget first, then design the acquisition PCB, embedded firmware, connectivity fallback, and OTA/admin controls in staged prototypes. Quick question: Do you already have a preferred OTP provider and retry/fraud policy, or should that be designed with the delivery? Also, do you already have the API and screen designs, or should the first milestone define the end-to-end mobile flow? Best, Dr. Syafiq

@OutsourceMan

Hi, CnEL India can support the companion mobile/cloud platform using React Native, with the embedded nRF52/BLE layer validated through an initial hardware POC. Our methodology: * Review the schematic, MCU, heart-rate sensor datasheet, BLE requirements and acceptance criteria. * Define firmware-to-mobile BLE data flow and measurement protocol. * Validate sensor sampling, filtering, averaging and power-management approach on the supplied hardware. * Implement BLE communication with reconnect handling and stability monitoring. * Build React Native iOS/Android app for pairing, live heart-rate display and historical graphs. * Implement local data storage, cloud synchronization and secure APIs. * Add background data collection, abnormal-reading alerts and CSV export. * Build a simple dashboard for live readings and daily averages. * Test BLE stability, data consistency and synchronization across devices. * Compare readings against the supplied reference device and document accuracy results. * Prepare iOS/Android builds, setup instructions, API documentation and testing procedures. We recommend starting with a focused hardware + BLE POC to validate sensor accuracy and connectivity before completing the full application.

@ciss26

Hello there, Hope you are doing well We can develop your complete Safety Band ecosystem, including the nRF52 embedded firmware, BLE communication, Flutter mobile application, cloud sync, alerts, analytics, and testing. We are with experience in IoT, BLE devices, Flutter apps, Node.js backends, cloud integration, real-time data processing, and hardware-software connectivity. Recommended Tech Stack - Firmware: C/C++ with Nordic nRF Connect SDK / Zephyr - MCU: nRF52 Series - Communication: Bluetooth Low Energy (BLE) - Mobile App: Flutter for iOS & Android - Backend/API: Node.js / NestJS - Database: PostgreSQL / Firebase - Cloud: AWS / Azure - Notifications: FCM + APNs - Charts: Real-time and historical heart-rate graphs Key Features Firmware - Heart-rate sensor integration - Continuous sampling - Filtering and averaging - BLE broadcasting - Battery monitoring - Power optimization - Reconnection/error handling - Stable background communication Mobile App - BLE device discovery and pairing - Live heart-rate monitoring - Historical charts - Daily average dashboard - Local storage - Cloud synchronization - Background data collection - Abnormal-reading alerts - Push notifications - CSV export - Device/battery status Thanks & Regards Dheeraj K.

@zainalitariq245

Hey there, You need both sides of the wearable covered, from nRF52 firmware handling heart rate filtering, averaging, power management and BLE, to a mobile app with live and historical readings, local storage, cloud sync and alerts. I would structure the firmware for stable continuous BLE operation and clean sensor processing, then use Flutter for a shared iOS and Android codebase. The app would include background collection, CSV export, graphs and the requested dashboard, with build and testing documentation included. One question: which heart rate sensor and cloud backend are you planning to use, or should the architecture keep both replaceable until the hardware details are provided? Looking forward to working together. My portfolio and client reviews, https://www.freelancer.com/u/zainalitariq245 Best regards, Zain Tariq.

@a4logic

Hello, As a seasoned developer with over a decade in the industry, I've taken numerous projects from concept to completion. I have significant experience in both hardware integration and mobile app development, making me an ideal candidate to bring your wearable safety band and companion app to life. With proficiency not just in Android but also in Flutter, I can build you a polished product that works seamlessly across iOS and Android devices. Furthermore, my expertise in writing robust firmware aligns well with your project's requirements. I'm familiar with the nRF52 series microcontrollers and passionate about the challenge they present. Your task of reading an averaging heart-rate data, managing power and maintaining a stable Bluetooth Low Energy connection resonates with my skills set. Lastly, as someone who takes great pride in their work being nothing short of perfect, you can expect impeccable deliverables from me. Heart-rate accuracy within ±3 bpm, BLE link stability above 95%, and compliance with App Store and Play Store requirements are metrics against which my solutions can meet without fail. Let's come together to transform your prototype into a top-notch solution that prioritizes user safety while being dependable and efficient. Reach out to me today, and let's get started on this journey toward a successfully finished project that exceeds all your expectations! Thanks!

@melikatfz

Hey, the nRF52 band streaming heart-rate data over BLE is the part I’d tackle first, since reliable sensor readings and an 8-hour connection are the foundation for the app. I’d handle the firmware filtering and power management, then build the companion app around live graphs, local storage, cloud sync, and background BLE collection. The tricky part is keeping BLE stable while the device sleeps and resumes data collection cleanly. Do you already have the exact heart-rate sensor selected?

@Eliteinno

hello, The hardest requirement, and where most BLE wearables fail, is 95% link stability over 8 hours against continuous heart-rate streaming plus low power, since those pull against each other: streaming constantly drains battery and floods the connection, while aggressive power-saving drops the link. So the real engineering is the BLE connection strategy, tuning connection intervals and batching sensor samples so the band sends efficiently rather than per-reading, which is what holds both the 8-hour stability and battery life together. On the app side, background data collection is the mirror problem, since iOS especially kills background BLE aggressively, so I'd design that around Core Bluetooth's background modes rather than assume Android's freedom. The ±3 bpm accuracy lives in the firmware filtering, so I'd implement solid signal filtering and motion-artifact handling on the nRF52 before averaging. Flutter gives both apps from one codebase with native BLE where needed, plus the graphs, local storage, cloud sync, alerts, and CSV export. Is this a medical/regulated device, or wellness-only, since that changes accuracy validation and store submission? And does cloud sync need to be real-time, or periodic batch uploads? have a nice day.

@hayteekeys

HI, KINDLY READ THROUGH MY PROPOSAL I will develop the complete embedded firmware for your wearable safety band and the companion mobile application, delivering reliable continuous heart-rate monitoring over BLE together with a polished iOS and Android experience. MY APPROACH ✅ nRF52 firmware: sensor reading, filtering, averaging, power management and stable BLE broadcasting ✅ Cross-platform or native mobile apps with real-time and historical heart-rate graphs ✅ Local storage, cloud sync, push alerts for abnormal readings and CSV export ✅ Background data collection and clean pairing flow ✅ Well-commented code, flashing instructions and full build documentation PROJECT EXPERIENCE - nRF52 / BLE wearable projects with continuous biometric sensing and power optimisation - Production mobile apps featuring real-time graphs, background sync and health-data export DELIVERABLES - Firmware source + flashing instructions - iOS and Android apps (or unified codebase) with build docs - Simple dashboard (live HR, daily averages, CSV export) - README covering setup, API and testing procedures QUESTIONS 1. Preferred mobile stack (Flutter, React Native, or native Swift/Kotlin)? 2. Specific heart-rate sensor model and any existing BLE service UUID preferences? 3. Target cloud back-end (Firebase, AWS, custom) or local-only for the first version? Ready to start as soon as the hardware schematic, sensor datasheets and preferred mobile approach are shared.

@invoketech

Hello, I checked your job post and understand that you need both nRF52-based wearable firmware and a companion iOS/Android app for reliable continuous heart-rate monitoring over BLE. Key features: nRF52 firmware and heart-rate sensor integration Signal filtering, averaging and power management Stable BLE data transmission and reconnection Flutter iOS & Android companion app Real-time and historical heart-rate graphs Local storage and cloud synchronization Background BLE data collection Abnormal heart-rate push alerts CSV data export Testing, flashing guide and complete documentation I have 10+ years of experience in mobile, BLE and connected-device development and can handle the firmware-to-app communication as one complete solution, including BLE reliability, data processing and production-ready mobile builds. I can also share relevant BLE/IoT project examples. Let we connect over call/chat for detail discussion. Thanks, Invoke Tech

@tonybhsl

Greeting!! Thank you for sharing your project with us. We understand that you are looking for an experienced team to develop both the nRF52 wearable firmware and companion iOS/Android application for continuous heart-rate monitoring. We have 20 years of experience in software and mobile application development, with expertise in Flutter, BLE, IoT, embedded systems, APIs, cloud backends, and real-time applications. We can handle the complete solution including heart-rate sensor integration, filtering/averaging, power management, BLE communication, device pairing, live and historical heart-rate graphs, local storage, cloud sync, background data collection, abnormal-reading notifications, and CSV export. We will build a reliable and scalable architecture, thoroughly test BLE stability and heart-rate accuracy against your reference device, and provide complete source code, flashing/build instructions, README, API documentation, and app-store submission support. We would like to review your hardware schematic and sensor datasheet over chat and finalize the technical approach, milestones, and cost. Please feel free to contact us. Thanking you, Deepika Sharma

@tshibsamuel477

Hi there, I carefully reviewed your wearable safety-band project, including continuous heart-rate acquisition, signal filtering, low-power operation, BLE communication, and the companion iOS/Android application with live data, history, alerts, cloud synchronization, and CSV export. I am a mechatronics engineer with almost half a decade of experience in embedded electronics, hardware prototyping, sensors, microcontroller-based systems, and interfaces such as SPI, I2C, UART, and USB. This background is directly relevant to the firmware side of the project, particularly reliable sensor acquisition, embedded data processing, BLE integration, and power-aware wearable operation. I understand that the complete solution must also meet measurable acceptance targets for heart-rate accuracy and long-duration BLE stability, with clear source code, build documentation, and test procedures. My embedded-systems background allows me to approach the device-side development and system integration efficiently and methodically. Please send me a message so we can discuss the project and start. Best regards, Samuel tshibangu

@kishanbwts

I’ve worked on wearable projects where reliable continuous heart-rate monitoring and stable BLE communication were key. To tackle your firmware, I’ll start by implementing sensor reading with real-time filtering and averaging to ensure readings stay within ±3 bpm. Power management on the nRF52 will be tuned to maintain BLE link stability above 95% for 8+ hours, based on similar low-power streaming challenges I’ve handled. For the app, a cross-platform approach like Flutter makes sense to deliver native-level UI/UX quickly on iOS and Android. I’ll implement pairing, real-time and historical graphs, local storage with background syncing, and push alerts for out-of-range values. One question: Do you have a preferred cloud backend, or should I suggest a lightweight, scalable option? Also, can you confirm which CSV format you want for export? I’ll provide clear documentation for firmware flashing, app builds, and usage to streamline testing and deployment. Ready to start building a smooth, robust heart-rate monitoring system that hits your performance targets.

@mughiraaa

Hello, I have already completed similar wearable, BLE, and mobile application projects, with strong experience in web development, APIs, and scalable software solutions. I can handle the nRF52 firmware, heart rate data filtering, averaging, power management, BLE communication, and the companion iOS and Android app with live graphs, history, cloud sync, alerts, and CSV export. Will you provide the exact heart rate sensor and reference device details along with the hardware schematic? I can quickly understand the requirements and deliver exactly what is needed. Let’s have a quick meeting to discuss the firmware, BLE flow, and mobile architecture. I will share my portfolio in chat I look forward to hear from you. Thanks Best Regards, Mughira

@MuhammadAsad108

✔ I deliver 100% work — 99.9% is not for me. ✔ Workflow Diagram Hardware Review ⟶⟶ nRF52 Firmware ⟶⟶ Sensor Filtering ⟶⟶ BLE Protocol ⟶⟶ Flutter App ⟶⟶ Local/Cloud Sync ⟶⟶ Alerts & CSV ⟶⟶ 8-Hour Testing ⟶⟶ Store Handover Key Highlights ✔ nRF52 embedded firmware architecture ✔ Continuous heart-rate sensor acquisition ✔ Filtering, averaging & power management ✔ Reliable BLE GATT communication ✔ Flutter iOS/Android companion app ✔ Live & historical heart-rate graphs ✔ Local storage + cloud synchronization ✔ Background BLE data collection ✔ Abnormal-reading push alerts ✔ CSV export, source & documentation I’ll first review the schematic, exact nRF52 MCU and sensor datasheet, then define sampling, filtering, BLE characteristics and power states. Accuracy will be validated against the agreed reference-device test procedure rather than assumed from raw sensor output. Best Regards, Asad Embedded Systems | BLE | Flutter | Mobile Apps

@shubhi8982

As a seasoned Full-Stack Developer with proven expertise in Android and iPhone mobile app development, your Safety Band & App project aligns seamlessly with my skills and experience. I have a comprehensive understanding of both low-level BLE firmware development and modern mobile development, which will be invaluable to designing the firmware for your wearable safety band and creating a complementary mobile application. Using my competencies in Flutter, React Native, Ionic as well as native Swift/Kotlin, I can guarantee unparalleled performance and solid UI designs for both iOS and Android platforms. Moreover, my extensive experience in API development and integrations is crucial in ensuring a seamless sync between your companion app, cloud backend, and wearable device.

@MuhammadUzair16

Hi I am an embedded systems engineer with over 16 years of experience developing connected products, including low-power sensor firmware, nRF52 BLE devices, mobile applications, and cloud-connected monitoring systems. I can handle the complete band-to-app workflow: reliable heart-rate acquisition and filtering, power management, stable BLE communication, background collection, local history, cloud sync, abnormal-reading alerts, graphs, and CSV export. I would use a shared Flutter codebase for iOS and Android unless your existing ecosystem favors native development. The work would be delivered in staged, testable builds with documented firmware flashing, app setup, APIs, and validation procedures. I can also support the wider consumer-product path from prototype refinement through production readiness. Heart-rate accuracy will be tuned and verified against your reference device, while BLE stability will be tested through extended runs. Do you already have a preferred cloud backend, and will a physical prototype be available for firmware testing? The quoted budget covers a focused first production-ready release based on the supplied hardware and finalized requirements. Please contact me to discuss details.

@jayantkumar314

As a seasoned Senior Software Engineer with over six years of hands-on experience in Android and mobile app development, I confidently believe I am the perfect fit for your Safety Band and App Coding project. My technical know-how in handling everything from building websites from scratch to hosting parallels well with the needs of your firmware and app aspects. I assure you of my full capabilities in the areas of Bluetooth Low Energy (BLE) technology, Swift, Kotlin, React Native, Flutter, and my penchant for exceeding expectations. Notably, my expertise extends to developing clear-cut APIs with robust authentication systems. This will ensure that users of your safety band have access only to permitted resources through a User-Friendly companion app as specified in the description. In addition, I have mastered various hosting platforms like AWS, Google Cloud and digital ocean where I will handle all the data processing both locally and on cloud for the smooth performance of the developed applications. My solid grounding in User Interface (UI) guidelines combined with your detailed Project Description means we can work together towards a common goal: transforming your prototype into a polished, production-ready device. Let's build an intuitive application alongside efficient firmware for your safety band which not only meets but exceeds the acceptance criteria set out. Choose me, and together we'll create an exceptional product with outstanding chemistry!

@NEHABHAT92

With a decade of software development experience, including nine years specifically in mobile app development, I have the expertise to optimize this corporate wearable project. My team and I at [Your Company] have an unrivaled proficiency in developing applications for Android and iOS, which makes us well-suited for the dual challenge of firmware programming and mobile app creation that your project requires. Furthermore, we are proficient with modern Bluetooth Low-Energy (BLE) protocols, having utilized them for several health-monitoring prototypes in the past. Our experience in e-commerce further exemplifies our ability to design user-friendly and reliable health-monitoring apps that store data locally and sync seamlessly with cloud backends. Our websites' responsiveness and designs can likewise be leveraged for crafting a clear-cut graphical interface on your mobile app's companion dashboard, displaying not just real-time and historical heart-rate graphs but also live updates on daily averages. Finally, as an added value aspect, we offer free 3-month support for existing developments which will aid you during troubleshooting and modifications beyond delivering mere source code. Our flexible cost structure also ensures that you receive our top-notch proficiency without burning through your budget. Choose us to transform your wearable prototype into a dynamic yet polished solution!