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I have a fully-built mobile application that runs on both iOS and Android, but a few critical items still need attention before the next store release. First, I want seamless in-app payments: Apple Pay on iOS and Google Pay (or the standard Google in-app billing) on Android. The checkout flow is already in place; your role is to wire up the official SDKs, handle tokenisation on the device, and hand the payment data back to my existing API. Second, several core features have started misbehaving. Users occasionally get stuck on the Login/Signup screen, push notifications are unreliable, and the current in-app purchase module throws errors on some devices. I need these three areas stabilised so onboarding is smooth, notifications arrive every time, and purchases complete without crashes or double charges. I will provide: • Current Xcode and Android Studio projects • API documentation and test credentials • Test accounts on both app stores for sandbox purchases Deliverables I expect from you: • Updated iOS build with Apple Pay fully integrated and tested • Updated Android build with Google Pay / Play Billing integrated and tested • Resolved bugs in Login/Signup, push notifications, and in-app purchases on both platforms • Clean, well-commented code committed back to my repository plus release-ready builds for TestFlight and Google Play Console I am happy to answer any architecture questions up front—just let me know what you need to get started.
Project ID: 40504549
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These are exactly the three areas that break apps before a release — payment integration, auth stability, and notification reliability. All fixable with the right approach.
$140 USD in 7 days
2.3
2.3
125 freelancers are bidding on average $160 USD for this job

Hello, As a renowned web service provider and IT company, we've amassed invaluable experience in the realm of iOS and Android app development. Handling intricate payment integrations is our specialty, proudly having worked with both Apple Pay and Google Pay API's, which aligns perfectly with your project requirements. By utilising our expertise, we can ensure that the tokenization process is seamlessly handled on-device, guaranteeing customer security. Moreover, our team has ample experience working with APIs and will readily integrate payment data back to your existing one. In addition to the payment aspect of this project, our diverse skill set also encompasses core mobile development functionalities such as handling app crashes, stabilising login/sign up components and optimising push notifications. Having faced similar issues in the past, we've developed an efficient troubleshooting mechanism for these challenges. I believe that we are uniquely positioned to handle your project and deliver results that not only meet but exceed your expectations. In working with us, you'd be engaging a team that understands your needs deeply and commits to excellent customer service throughout the project lifecycle. Choose us and let's turn your vision into a reality together! Thanks!
$130 USD in 2 days
8.6
8.6

Dear Client, I am interested in this project. Lets connect to discuss the project in detail so that we can proceed with the . Thanks
$140 USD in 7 days
8.4
8.4

Hello there, I will integrate Apple Pay and Google Pay into your existing checkout flow — wiring up the official SDKs, handling tokenization, and passing payment data back to your API. Alongside that, I will stabilize the Login/Signup screen, push notifications, and in-app purchase module on both platforms. For push notifications, I will audit the token refresh logic first — unreliable delivery often stems from stale device tokens that were never re-registered after app updates. Questions: 1) Is the app built natively or using a cross-platform framework like Flutter or React Native? 2) Are push notifications handled through Firebase Cloud Messaging on both platforms, or a different service? Looking forward to your response. Best regards, Kamran
$90 USD in 5 days
8.5
8.5

I have built and maintained similar iOS and Android apps involving Apple Pay, Google Pay/Play Billing, authentication flows, push notifications, and in-app purchase troubleshooting. I can integrate the payment SDKs, resolve the critical issues, and deliver release-ready builds with full source code updates. Is the app built natively (Swift/Kotlin) or using a cross-platform framework such as Flutter or React Native?
$200 USD in 7 days
8.1
8.1

Hi, I can help you stabilise your existing iOS and Android apps and fully integrate Apple Pay + Google Pay / Play Billing while fixing the critical production issues you’re facing. ✔ Apple Pay integration using native iOS SDK (Payment Request / Stripe or native gateway) ✔ Google Pay / Play Billing integration following Google’s latest billing policies ✔ Secure tokenisation flow with backend handoff to your API ✔ Fix for Login/Signup flow freezes (state handling, async routing, session persistence) ✔ Push notification reliability improvements (FCM/APNs handling, background/foreground states) ✔ In-app purchase crash fixes (receipt validation, duplicate charge prevention, edge-case handling) ✔ Device-level testing across multiple OS versions ✔ Clean, well-commented code pushed back to your repo ✔ Release-ready builds for TestFlight + Google Play Console Deliverables Updated iOS build (Apple Pay + fixes) Updated Android build (Google Pay / billing + fixes) Stable authentication + notification system Fully tested payment flow (sandbox + live-ready) Deployment-ready commits I’ll also review your current architecture quickly before implementation to ensure payments, auth, and notifications don’t conflict with existing logic. If needed, I can work with Stripe / Adyen / native billing depending on what your backend already supports. Ready to start immediately once I get access to your repositories and API docs. Best regards,
$140 USD in 7 days
8.1
8.1

Hi, I have extensive experience in mobile app development and can address the critical items in your iOS and Android payment integration project. I will seamlessly integrate Apple Pay on iOS and Google Pay on Android, ensuring a smooth checkout process. Additionally, I will stabilize the Login/Signup functionality, fix push notification issues, and resolve errors with in-app purchases. I will provide updated builds with the payment systems integrated and thoroughly tested, along with clean, well-commented code committed to your repository. I am ready to start immediately and can ensure a successful outcome for your mobile application. Let's discuss further details to get started promptly. Thank you.
$90 USD in 2 days
7.8
7.8

Hi, We’ve developed several mobile apps with integrated payment systems, including Apple Pay and Google Pay. We also have extensive experience with Firebase and OneSignal for reliable push notifications. For your project, we can start with a quick 10-minute call to discuss the existing code and clarify any immediate questions. This way, we can hit the ground running and deliver results faster. We’re committed to providing a fully functional product, not just fixing individual bugs. We take a holistic approach, ensuring that all related features work seamlessly together. Let’s schedule a call to discuss your project in more detail. I usually respond within 10 minutes. Best regards, Adil
$154 USD in 7 days
7.6
7.6

Hello, Your project “iOS-Android Payment Integration Fixes” fits our expertise. We can integrate Apple Pay & Google Pay, fix authentication, push notification, and in-app purchase issues, and deliver stable release-ready builds. Doomshell Software Pvt. Ltd. | 20+ Years of Experience in mobile app development and payment integrations. We can help with: ✔ Apple Pay integration on iOS using official SDKs ✔ Google Pay / Play Billing integration on Android ✔ Secure payment tokenization and API integration ✔ Login/Signup flow debugging and stabilization ✔ Push notification reliability improvements ✔ In-app purchase error resolution and testing ✔ Release preparation for TestFlight and Google Play We’re experienced with: ✔ Swift, Kotlin, Java, and cross-platform mobile apps ✔ Apple Pay, Google Pay, and In-App Purchases ✔ Firebase Push Notifications and FCM ✔ REST API integrations ✔ Mobile app debugging and performance optimization Deliverables: ✔ Fully tested payment integrations ✔ Fixed authentication and notification issues ✔ Stable in-app purchase workflow ✔ Clean, documented code and release-ready builds Quick Questions: 1. Is the app built natively or using Flutter/React Native? 2. Which push notification service is currently being used (FCM, OneSignal, etc.)? Regards, Doomshell Software Pvt. Ltd.
$200 USD in 7 days
7.5
7.5

Hi, I can help resolve your iOS and Android app issues, including Apple Pay/Google Pay integration, checkout flow errors, login/signup problems, push notifications, and in-app purchase functionality. With 6+ years of experience in mobile app development and API integrations, I focus on identifying root causes quickly and delivering stable, production-ready fixes. My goal is to ensure a smooth user experience and reliable app performance across both platforms. Looking forward to discussing the details. Best regards, Taher
$110 USD in 7 days
6.8
6.8

Hello There!!! ★★★★ (Fixing in-app payments + stabilizing core mobile app flows for iOS & Android release readiness) ★★★★ Project understanding: I understand you already have a working iOS and Android app, and you need proper integration of Apple Pay and Google Pay / Play Billing. Along with this, critical issues in login/signup, push notifications, and in-app purchases must be fixed to ensure smooth onboarding and stable production release. Services: ⚜ Apple Pay integration using iOS SDK ⚜ Google Pay / Play Billing integration on Android ⚜ secure payment tokenisation & API wiring ⚜ login/signup flow debugging & fix ⚜ push notification reliability improvements ⚜ in-app purchase crash & double charge fixes ⚜ TestFlight & Play Store release builds I have exp in mobile app development, payment gateway integration and debugging production apps on both iOS and Android, including fixing onboarding and purchase flow issues. Approach: I will first reproduce issues on both platforms, integrate official payment SDKs, stabilize auth flow, fix notification delivery, and thoroughly test sandbox transactions before release builds. Let’s connect and I can start immediately to prepare your app for a clean store release. Warm Regards, Farhin B.
$890 USD in 10 days
6.8
6.8

I'm Vimal, and I'm excited about the possibility of fixing the payment integration issues on your mobile app. With over a decade of experience in both Android and iOS development, I have successfully completed numerous similar projects focusing on enhancing app performance while resolving in-app purchase and payment gateway challenges. My proficiency with Xcode, Android Studio, and knowledge of tokenization will ensure that Apple Pay on iOS and Google Pay/Play Billing on Android are seamlessly integrated into your application while remaining in line with their official SDKs. Equally important is my ability to handle bug fixing - we'll quickly sail through those pesky problems causing stuck Login/Signup screens, unreliable push notifications, and in-app purchase errors. Moreover, the well-commented clean code that I deliver will not just fix existing issues but will make future maintenance easier as well. By entrusting me with your project, expect updated builds where users can login/signup without any interruptions, notifications arrive without fail, and purchases complete without any crashes or double charges. As an added benefit, my proficiency not only ends at mobile development but also includes effective digital strategies - I can offer insights into API integration to further enhance user experience. Let's transform your vision into reality!
$200 USD in 7 days
6.4
6.4

Hey there, Regarding your mobile app project, the payment integration's tokenisation and API handoff can easily become bottlenecks if not handled efficiently. I ensure each payment SDK is correctly wired to deliver seamless transactions and prevent any data hiccups. In a past project, I refined a similar integration, which resulted in a 30% reduction in payment failure rates. I'll include 30 days of post-deployment bug-fixing to keep everything smooth. Quick question: what's the current error handling mechanism for payment failures? Let's discuss how I can help.
$200 USD in 4 days
5.9
5.9

I see you're looking for help with payment integration issues in your mobile app for both iOS and Android. I've worked on similar projects, and I understand how critical it is to resolve these items quickly to keep your app running smoothly. With around 10 years of experience in mobile app development and payment gateway integration, I can help identify the problems and implement the necessary fixes effectively. Some similar things I've built include a regional booking platform for a tutoring company, an internal CRM for a property agency, and a React Native field-reporting app. Let’s get this sorted out so your users can have a seamless payment experience. Could you please clarify the following questions to help me better understand the project? Q1: What specific payment gateways are currently integrated, and what issues are you experiencing with them? Q2: Are there any existing error messages or logs that could provide insight into the problems? Q3: Do you have a preferred timeline for resolving these critical fixes?
$200 USD in 2 days
6.6
6.6

Hi, if you have digital good then go with in-app purchase or you have physical item to sell then will use payment gatway like stripe, paypal etc I can handle both having 8 years of experience in the field of mobile app development and mange payment in different app. Let's discuss.
$140 USD in 7 days
6.3
6.3

Proposal generation failed.
$175 USD in 2 days
6.0
6.0

Warm Hello! Your app is already close to release, which makes stability and payment integration the highest priorities. I have over 9 years of experience in this field, working with iOS and Android applications, payment gateways, in-app purchases, push notifications, and production-ready mobile releases. Here's how I can help: • Integrate Apple Pay on iOS using official Apple frameworks and best practices • Implement Google Pay and/or Google Play Billing on Android based on your existing purchase flow • Securely handle payment tokenization and pass payment data to your existing API • Diagnose and fix Login/Signup issues causing users to become stuck during onboarding • Investigate and stabilize push notification delivery across devices and operating system versions • Resolve in-app purchase errors, failed transactions, duplicate charges, and device-specific issues • Deliver clean, documented code with release-ready builds for TestFlight and Google Play Console • Perform end-to-end testing using sandbox accounts before deployment
$140 USD in 7 days
6.0
6.0

<<<✔Consider it DONE✔>>> YO! I understand your project and I'm eager to help. With the complexity that comes with cross-platform mobile applications, having a reliable and experienced developer like myself, LUI, is imperative. I have a solid background in Mobile App Development and PHP which make me well-equipped for integrating seamless in-app payments and fixing core features issues. Restoring stability to your iOS and Android platforms means precisely wiring up Apple Pay on iOS, Google Pay on Android while implementing tokenization on both devices. Additionally, I am well-versed in handling API integration which is crucial for sharing with your existing API after tokenization. Looking forward to being part of your project! You will surely be impressed by my work! Not sure what the next step is? I offer free and professional consultation -- I'm just a text away. All the very best, Josh
$140 USD in 2 days
5.5
5.5

✋ Hi There!!! ✋ The Goal of the project:- FIX CROSS PLATFORM PAYMENT INTEGRATION AND STABILIZE IOS AND ANDROID APP FUNCTIONALITY FOR RELIABLE PRODUCTION RELEASE I carefully reviewed your complete requirement and understand you need secure Apple Pay and Google Pay integration along with fixing critical issues in login flow, push notifications, and in-app purchases to ensure a stable release on both iOS and Android stores. With 9+ years experience as a full stack developer, I am the best fit because I have strong expertise in mobile payment SDK integration, debugging production apps, and fixing cross platform issues. 1 Apple Pay and Google Pay / Play Billing integration with secure tokenization and API handling 2 Bug fixing for login signup flow, push notifications, and in-app purchase stability across devices 3 Clean code updates with TestFlight and Google Play release ready builds I will provide UI testing, database validation, payment integration, debugging, and full source code delivery with production ready builds. I have completed similar mobile payment integration and app stabilization projects. Looking forward to chat with you for make a deal Best Regards Elisha Mariam
$111 USD in 11 days
5.0
5.0

Hi! The mix of payment fixes, onboarding bugs, and unstable notifications rings familiar—especially making Apple Pay and Google Pay work smoothly and getting users past Login/Signup without glitches. The risk is missing device-specific edge cases, which is often why in-app purchases break or double-charge. I’ve handled similar mobile payment and notification bugs for live apps in both stores—recent example is the Wish App (React Native, running on iOS and Android with integrated payments and alerts). One thing to clarify: Are you using React Native, Flutter, or pure native code? This affects which SDKs I’ll need to wire up for payments and notifications. Happy to do a walk-through of your codebase and send back a bug-by-bug action plan for free. You can check more of my mobile work at work.techindika.com. — Pradeep
$140 USD in 7 days
5.1
5.1

Hi, I've thoroughly reviewed your needs for seamless Apple Pay and Google Pay integration alongside stabilizing core app features. With extensive experience in iOS and Android app development and PHP backend interaction, I understand the nuances of handling payment SDK wiring, secure tokenization, and API communication to ensure flawless checkout flows. I will also focus on resolving login/signup glitches, push notification reliability, and in-app purchase stability to enhance user onboarding and prevent payment errors or crashes. Providing test builds promptly through TestFlight and Google Play Console aligns well with my commitment to clean, maintainable code and smooth deployment. Let’s start by reviewing your current setup and API details to tailor the integration efficiently. What specific error patterns have you observed in the in-app purchase crashes across different devices? Thanks,
$155 USD in 20 days
5.1
5.1

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