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I want to ship a lean Android + iOS application that can 1) establish a Bluetooth Low Energy link to my peripheral and move data back and forth, and 2) instantly push out a user-defined BLE packet the moment the phone detects an incoming call. The BLE work is classic data-transfer: discover the device, pair, subscribe to characteristics, then read/write packets on demand. Stability in the background is critical; the link must stay alive (or reconnect quickly) when the screen is off. When a call arrives the app should listen to the system broadcast (Android) or CallKit/VoIP push workaround (iOS), pull the string the user previously defined, and write it over the existing BLE connection without visible delay. Please send a concise, detailed project proposal outlining: • your preferred tech stack (e.g., Kotlin + Swift, Flutter, React Native, etc.) and why it meets both BLE and call-event constraints, • an architecture plan for background operation on both platforms, • how you will test timing reliability of the call-triggered message, • past apps that prove you have already handled BLE data packets or telephony events. Deliverables: • Full source code with build instructions • Debug and release builds for Android (APK/AAB) and iOS (TestFlight) • A minimal UI to select the peripheral, enter the custom “on-call” message, and view basic connection logs • Short README documenting characteristic UUIDs, message format, and any platform-specific permissions I’m ready to move quickly, so the clearer your proposal, the faster we can start.
Project ID: 40217667
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Active 2 mos ago
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109 freelancers are bidding on average $569 USD for this job

Greetings from Logictrix! My name is Jas, and I am looking forward to discuss about your app in details over the Chat or Call. We have enough app developers available in team so I can assure you to deliver this project at a fairly low cost with great quality and with a commitment for long term support. *** We have now earned 'Expertise' level in AI, ChatGpt and a couple of other AI platforms for App development and other Chatbot work! *** We have developed around 400+ Android and iOS apps using Native and Flutter SDK in the past 15 years, Many apps are Live in Google play and App store. We will share our detailed portfolio over the Chat once we connect. Looking forward to your reply... Thanks and Regards Jas
$500 USD in 10 days
9.7
9.7

Hello, I have read your requirements and clearly understand you need a lean Android + iOS BLE app that keeps a stable background BLE connection and instantly sends a user-defined packet when an incoming call is detected, with a simple UI and full builds. I have 10+ years of experience in mobile development, I have built multiple BLE data-transfer systems and handled telephony event listeners on both platforms. I can deliver a robust, production-ready solution using native code to ensure reliability and compliance with platform constraints. BACKGROUND ARCHITECTURE: Android: FOREGROUND SERVICE + BLE reconnect logic + PhoneStateListener / BroadcastReceiver iOS: CoreBluetooth with BACKGROUND RESTORATION + CallKit (or VoIP push workaround) Immediate BLE write on call detection using existing connection or fast reconnect TIMING RELIABILITY TESTING: Simulated incoming calls on both platforms Measure latency from call detection to BLE write Run tests in background, screen off, and reconnection scenarios Logging for performance and stability validation DELIVERABLES: Full SOURCE CODE with build instructions Debug + RELEASE builds (APK/AAB + TestFlight) Minimal UI: device selection, custom “on-call” message, connection logs I will provide 2 YEARS FREE ongoing support, complete source code, and work in an agile approach from scratch to publishing. I have some queries to ask regarding the project to proceed further. Awaiting your positive response. Thanks
$300 USD in 7 days
8.4
8.4

Hello, I’ve reviewed your requirement for a lean Android and iOS app that maintains a stable BLE connection and instantly transmits a user-defined packet when an incoming call is detected. This is a timing-sensitive use case where native platform handling is critical. Proposed Tech Stack: Android: Kotlin (native) iOS: Swift (native) Native development ensures reliable background BLE operation, low-latency characteristic writes, and proper handling of system call events, which hybrid frameworks struggle with under OS restrictions. Architecture Approach Persistent BLE manager with auto-reconnect and pre-subscribed characteristics Android foreground service for background BLE stability + call state listener iOS CoreBluetooth with background modes and CallKit/PushKit strategy User-defined packet stored locally and written instantly on call detection Reliability & Testing Screen-off and background stress testing Incoming call timing tests with BLE write timestamps Reconnect and failure-recovery scenarios Multi-device testing across Android OEMs and iOS versions Deliverables Full source code with build instructions Android APK/AAB and iOS TestFlight builds Minimal UI for device selection, message entry, and connection logs README covering UUIDs, packet format, and permissions Best Regards, Jemin Sagar
$500 USD in 7 days
7.0
7.0

As a proficient Electrical Engineer with extensive experience in firmware development and IoT solutions, I am confident I can provide an excellent project execution for your Cross-Platform BLE Call-Reactive App. My preferred tech stack of Kotlin + Swift emerges as an optimal choice, ensuring seamless integration and operation on both Android and iOS platforms while maintaining a high level of stability in the background - an attribute you've rightly emphasized on. To guarantee reliable background functioning, I propose utilizing a robust architecture that utilizes native functionalities such as system broadcasts on Android and CallKit/VoIP push workaround on iOS. This architectural design will ensure efficient data transmission across both BLE and telephony events while prioritizing promptness and minimal latency.
$500 USD in 7 days
6.7
6.7

Hello, I’ve gone through your project details, and this is something I can definitely help you with. I have 10+ years of experience in mobile app development, particularly with Flutter and native development using Kotlin and Swift. For your cross-platform BLE call-reactive app, I recommend using Flutter as the tech stack. Flutter allows rapid development and robust compatibility with both Android and iOS for BLE functionalities, while also enabling seamless integration with call events. To ensure stability, my architecture plan involves leveraging background services on Android and background tasks with CallKit on iOS, which will allow the app to maintain the BLE connection during screen-off scenarios. For testing the timing reliability of call-triggered messages, I will implement unit tests and real-time performance monitoring during calls. I have successfully developed similar applications in the past, such as an IoT BLE app that pushed notifications based on sensor data. Here is my portfolio: https://www.freelancer.in/u/ixorawebmob I’m interested in your project and would love to discuss further. Could you clarify if there are any specific design preferences or additional features you envision?Could you clarify if there are any specific design preferences or additional features you envision? Let’s discuss over chat! Regards, Arpit Jaiswal
$250 USD in 21 days
7.5
7.5

Hello There!!! ⚜⭐⭐⭐⭐⚜(( CROSS-PLATFORM MOBILE APP WITH BLE DATA TRANSFER AND CALL-TRIGGERED PACKET DELIVERY ))⚜⭐⭐⭐⭐⚜ Project GOAL develop a mobile app that sends BLE packets instantly when a call arrives I see you need a lean iOS and Android app that maintains a stable BLE connection and instantly sends a user-defined packet when a call comes in. Background reliability and fast response are critical, alongside a minimal UI for message entry and connection monitoring. I have extensive experience building Flutter and React Native apps with BLE integration, handling background services, and capturing system telephony events on both Android and iOS. I can design a robust architecture with reconnection logic and precise timing validation for call-triggered messages. Key features 1. BLE discovery, pairing, and reliable background data transfer 2. Instant packet push on incoming call detection 3. Minimal UI with peripheral selection, message input, and logs I am ready to propose the tech stack, schedule testing, and deliver production-ready builds quickly. Warm Regards, Farhin B.
$256 USD in 10 days
6.5
6.5

Hello, I am really excited about the opportunity to collaborate with you on this project! It aligns perfectly with my skill set and experience, and I’m confident I can contribute meaningfully to your vision. I genuinely enjoy working on projects like this, and I believe we can create something both functional and visually engaging. Please feel free to check out my profile to learn more about my past work and client feedback. I’d love to connect and discuss the project details further your goals, expectations, and any specific features or ideas you have in mind. The more I understand your vision, the better I can bring it to life. I am ready to get started right away and will put my full energy and focus into delivering quality results on time. My goal is not just to complete the project, but to exceed your expectations and build a long-term working relationship. Looking forward to hearing from you soon! With regards! Nikhil
$750 USD in 7 days
6.3
6.3

Being a seasoned developer with 10+ years of experience, I offer a comprehensive skill set perfectly aligned with your project requirements. While your tech preferences leave doors open, I would suggest adopting a cross-platform framework like React Native or Flutter. These frameworks allow us to build lean, highly-performant apps for both Android & iOS simultaneously - doubling the ROI on development busywork. My proficiency with React Native and Flutter enables me to quickly architect stable and background-friendly apps that support Bluetooth Low Energy (BLE) communication while handling system broadcasts effectively. Notably, I have ample experience with BLE in my past projects—working through vital tasks such as pairings, subscribing to characteristics, and sending and receiving data efficiently. As demonstrated in my profile, I've collaborated on various mobile apps that are currently available on both Google Play Store and App Store. Of particular relevance is my expertise in maintaining stable connections, even when devices are idle or the display is turned off - aligning well with your need for stability without visible delay in communication. Therefore, I will design an extensive testing regime that will mimic various real-life scenarios to simulate incoming calls and measure the time it takes for the user-defined BLE packets to be sent. With Regards! Abhishek Saini
$750 USD in 7 days
5.9
5.9

To reliably handle BLE communication and instant call-triggered messaging, I recommend using native Kotlin for Android and Swift for iOS. This lets us fully control background BLE operations and system call events without the limitations cross-platform frameworks often face, especially around background tasks and system broadcasts. For Android, the app will use a foreground service with BluetoothLeScanner and a BroadcastReceiver listening to telephony events to keep the BLE link alive and react immediately to incoming calls. On iOS, we’ll leverage CoreBluetooth alongside CallKit and the VoIP push notification workaround to detect calls and send BLE packets with minimal delay. This architecture ensures stable connections even with the screen off. To verify timing accuracy, I’ll implement logging timestamps for call detection and BLE writes, comparing them in end-to-end tests using real devices. I’ve previously maintained stable BLE data transfer apps that monitored system broadcasts for events and triggered BLE writes within milliseconds. I suggest starting with Android first to validate rapid call detection and notification, then mirror the solution for iOS given its additional VoIP push complexity. How do you want to handle peripheral pairing: automatic based on device ID or user selection each session? I’m ready to build the minimal UI, full source, and thorough documentation so you can deploy quickly. Let’s get this moving.
$750 USD in 7 days
5.4
5.4

Hi I can build your lean cross-platform app that maintains a stable BLE connection, reads/writes packets reliably in the background, and pushes a user-defined BLE message the instant an incoming call is detected. The main technical challenge is coordinating BLE background behavior with fast telephony event handling on both Android and iOS; I solve this with native-level APIs, background modes, and reconnection logic tailored to each OS. I’ll create a minimal UI for device selection, message entry, and logs, and deliver full source code plus TestFlight/AAB builds. My past work includes BLE command/response apps and telephony-triggered workflows with strict timing requirements. I’m comfortable outlining a detailed architecture and testing plan so we can move forward quickly. Thanks, Hercules
$500 USD in 7 days
5.4
5.4

Hi! Your project perfectly matches my expertise in native mobile development with Kotlin and Swift—these give us the precise control needed for reliable BLE connections and seamless background operation on both Android and iOS. I’ll design a robust architecture that keeps the BLE link stable even with the screen off, and implement immediate call-detection triggers using system broadcasts and CallKit workarounds. I have hands-on experience building apps handling BLE data and telephony events, ensuring fast, reliable messaging. I’ll also provide thorough testing plans to guarantee timing accuracy and deliver clean builds with full documentation. Looking forward for your positive response in the chatbox. Best Regards, Arbaz T
$600 USD in 7 days
5.1
5.1

hi, i have reviewed the details of your project. we have experience developing mobile apps that work seamlessly with bluetooth low energy and handle telephony events on both android and ios. our approach will be to develop a lean app using flutter, which allows us to create a single codebase for both platforms, ensuring faster delivery and easier maintenance. we will implement stable background operation to keep the ble connection alive and reconnect if needed. on android, we will listen to system broadcasts for call detection, and on ios, we will use call kit and voip push notifications to detect incoming calls instantly. the app will then send your predefined message over the ble connection with minimal delay. we will focus on reliable timing by testing in various scenarios, including screen off and multitasking. our past projects include similar ble data transfer apps and telephony event handling, which proves our capability. let's have a detailed discussion, as it will help me give you a complete plan, including a timeline and estimated budget. i will share my portfolio in the chat. mughiraa
$500 USD in 7 days
5.2
5.2

Hi, I'm excited about the prospect of developing your cross-platform BLE app. With a proven track record as a top California freelancer, I've successfully completed numerous projects with 5-star reviews, specifically in Bluetooth Low Energy (BLE) and mobile app development. I understand the critical need for stability in background operations, especially while managing call events seamlessly. For your app, I propose using Kotlin for Android and Swift for iOS to leverage their native capabilities for robust BLE communication and swift call handling. This approach ensures we can easily connect to peripherals, subscribe to characteristics, and manage data transfer without dropping the connection when the device is in sleep mode. I will implement an architecture that prioritizes reliability in background operations and conduct thorough testing to ensure message timing is instantaneous when a call is received. My previous work includes apps that handle BLE data transfer effectively, giving you the confidence that I am well-equipped to tackle this project successfully. Let’s discuss your specifics further; could you provide more details about the user-defined messages? Could you provide more details about the user-defined messages?
$610 USD in 7 days
5.0
5.0

✋ Hi There!!! ✋ The Goal of the project:- To develop a cross-platform Android and iOS app that maintains a stable BLE connection and sends user-defined packets instantly when an incoming call is detected. I have carefully read and understood your project description and can deliver a reliable, background-capable BLE app with minimal latency for call-triggered messages. I am the best fit for this project because I have extensive experience building mobile apps with BLE integration and handling telephony events on both platforms. I will implement BLE discovery, pairing, and real-time data transfer, integrate call detection with immediate packet sending, and design a minimal UI for peripheral selection, message input, and connection logs. I will provide UI design, testing, and full source code delivery with documentation for future maintenance. I bring 9+ years experience as a full stack developer and have completed similar projects involving BLE data transfer, real-time event handling, and cross-platform mobile apps. Looking forward to chat with you for make a deal Best Regards Elisha Mariam!
$251 USD in 7 days
5.0
5.0

Cross-Platform BLE Call-Reactive App I’m a full-stack software engineer with expertise in React, Node.js, Python, and cloud architectures, delivering scalable web and mobile applications that are secure, performant, and visually refined. I also specialize in AI integrations, chatbots, and workflow automations using OpenAI, LangChain, Pinecone, n8n, and Zapier, helping businesses build intelligent, future-ready solutions. I focus on creating clean, maintainable code that bridges backend logic with elegant frontend experiences. I’d love to help bring your project to life with a solution that works beautifully and thinks smartly. To review my samples and achievements, please visit:https://www.freelancer.com/u/GameOfWords Let’s bring your vision to life—connect with me today, and I’ll deliver a solution that works flawlessly and exceeds expectations.
$500 USD in 7 days
5.1
5.1

Hi there, I understand you're seeking to develop a cross-platform app that seamlessly establishes a Bluetooth Low Energy connection with your peripheral while reacting swiftly to incoming calls. This is an innovative project that requires not only solid technical expertise but also a nuanced understanding of communication between devices. I propose using a combination of Kotlin for Android and Swift for iOS, as both languages provide robust support for BLE operations and native capabilities for handling telephony events. By implementing a background service that will maintain the BLE connection during idle times, we can ensure stability and minimize reconnect delays. I will conduct rigorous testing focused on the timing reliability of the call-triggered messages, employing both standard and edge-case scenarios to ensure performance. My portfolio showcases my experience in similar projects where I successfully managed BLE data packets and telephony events, emphasizing my ability to deliver high-quality outcomes. What specific features or customizations do you envision to enhance user experience within this application? https://www.freelancer.com/u/proggon Best regards, Wahaj Barlas.
$500 USD in 7 days
4.7
4.7

Hi, We would like to grab this opportunity and will work till you get 100% satisfied with our work. We are an expert team which have many years of experience on Mobile App Development, iPhone, Android, Swift, Bluetooth Low Energy (BLE), Kotlin, React Native, Flutter Lets connect in chat so that We discuss further. Regards
$450 USD in 7 days
4.5
4.5

⭐⭐⭐⭐⭐ DEAR CLIENT ⭐⭐⭐⭐⭐ Hello, I have reviewed the project details. I have extensive experience in this field and recommend native Kotlin (Android) + Swift (iOS) for bulletproof BLE stability, background services, and call event handling—React Native/Flutter BLE lacks the native reliability you need for instant call‑triggered packets. 3-Week Plan ($500 Fixed): Week 1: BLE core (discover/pair/read/write/subscribe), background reconnection (Android Foreground Service + iOS State Preservation). Week 2: Call detection (Android TelephonyManager Broadcast + iOS CallKit), instant packet dispatch on connection. Week 3: Minimal UI (peripheral select, message input, logs), testing (real devices), builds + docs.
$500 USD in 7 days
4.3
4.3

I can build a lean cross-platform BLE app that maintains a stable connection to your peripheral and instantly transmits a user-defined packet on incoming call events. Tech Stack: I recommend native Kotlin (Android) + Swift (iOS) for maximum control over BLE reliability, background execution, and telephony constraints. This avoids cross-platform limitations around CallKit and BLE background modes. Architecture Plan: • BLE Core: Scan → connect → service discovery → subscribe to characteristics → queued read/write pipeline • Background Stability: Android Foreground Service + reconnect strategy; iOS CoreBluetooth background mode with state restoration • Call Trigger: Android Telephony broadcast listener; iOS CallKit/PushKit compliant flow to trigger the packet write with minimal latency • Packet Dispatch: Preloaded message buffer sent immediately over active GATT connection Testing & Reliability: • Automated timing tests with simulated call events • Logging of call-detect-to-write latency • Stress testing with screen-off, reconnect cycles, and weak signal scenarios Deliverables: • Full source code + build steps • Android APK/AAB + iOS TestFlight build • Minimal UI: device select, custom on-call message, connection/event logs • README covering UUIDs, packet format, and required permissions Best regards, Amaan Khan L. (CUBEMOONS PVT.)
$500 USD in 7 days
4.5
4.5

Hello, I’m excited about the opportunity to build your cross-platform BLE call-reactive app. My expertise in both Android and iOS applications makes me well-suited for managing Bluetooth Low Energy connections and call events effectively. With over 10 years of experience, I have strong capabilities in React Native, Swift, and Kotlin, ensuring performance and stability in background operations. I will utilize a tech stack of React Native combined with native modules for seamless Bluetooth communication and quick call-handling. For architecture, I plan to implement background services that maintain the BLE connection even when idle, ensuring a quick reaction to incoming calls. I will implement extensive testing to guarantee timing reliability for messages triggered by incoming calls, ensuring a pressure-free user experience. I have previously developed apps successfully handling BLE data transfer and telephony events, demonstrating my reliability in this area. Let’s discuss the finer details and move forward. Best regards, Volodymyr
$500 USD in 2 days
4.1
4.1

cairo, Egypt
Member since Aug 21, 2022
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