I’m a Flutter developer with 4 years of experience building, fixing, and scaling Android and iOS apps using Flutter and Firebase.
I help startups and businesses:
Build Flutter apps from scratch
Fix bugs and performance issues in existing apps
Implement clean UI from Figma or designs
Integrate Firebase authentication, Firestore, and real-time features
Connect REST APIs and third-party services
Prepare and publish apps to the App Store and Play Store
I’ve delivered Flutter apps in domains like ride-sharing, prayer times, productivity tools, and utility apps, focusing on stability, scalability, and fast delivery.
I communicate clearly, work efficiently, and deliver clean, maintainable code — not quick hacks.
Tech stack:
Flutter, Dart
Firebase (Auth, Firestore, Storage, Realtime DB)
REST APIs, Push Notifications
Google Maps
State Management (Provider, Riverpod, Bloc)
Native Code implementation (Swift UI , Kotlin)
If you need a reliable Flutter developer for a small task or a long-term project, feel free to invite me.
App Development
Mobile App
Hybrid App Development
Dart
Flutter
Android App Development
API Integration
iOS Development
iOS
Firebase
Mobile App Redesign
Mobile App Design
Mobile UI Design
Payment Gateway Integration
Flutter Stack
Theo S.
London, United Kingdom
$60/hr
5.0
74 jobs
"esteemed contractor", "brings new insights and plussed-up solutions", "massive asset to our team"
10+ years✓ $400k+ earnings✓ 4000+ hours✓ Individual freelancer✓
Certified IBM Machine Learning Professional
✅ Clients have been impressed by my professional approach, ability to complete tasks ahead of schedule, and deep knowledge of iOS development.
✅ Exceptional problem-solving skills, innovation, self-management and excellent communication abilities.
✅ An active contributor to GitHub.
Some of my key success areas are:
✅ Integrating AI and machine‑learning models into iOS apps.
✅ Updating or fixing older, defunct apps written in Objective‑C or Swift.
✅ Using and integrating with backend services such as REST APIs.
Core skills (not an exhaustive list)
✅ Worked with HealthKit, CoreBluetooth, CoreGraphics, UIKit, SwiftUI, CoreLocation, In‑App Purchases, CoreData, and many other iOS frameworks.
✅ Built geospatial apps, maps, R‑Tree algorithms, and large‑scale geo‑data solutions on iOS.
✅ Skilled with UI/UX animation tools such as PaintCode, and with embedding assets in CoreGraphics efficiently.
✅ Experienced with AI technologies such as MyScript (hand‑writing recognition) and staying familiar with newer platforms such as OpenAI, Anthropic, etc.
✅ Proficient in using architectural patterns such as Model‑View‑ViewModel + Coordinator (MVVM‑C) and applying them in UIKit and MapKit for geospatial apps, binding data and presentation with RxSwift and Combine.
✅ Skilled in creating Swift Packages and incorporating code from C/C++, Objective‑C, and Swift. This provides a simple way for other developers to use mathematical or statistical libraries without dealing with platform‑specific, deprecated‑code, or linkage issues, while preserving unit tests for macOS builds.
✅ Proficient in Python 3 and using it to prepare, analyze, or transform data for AI/ML models before migrating a pre‑existing model to the macOS/iOS AI/ML toolchain (Core ML, Vision, Speech, etc.) via .mlmodel files.
The AI Co‑worker’s policy
✅ Always adhere to the client’s AI policies when using agentic‑AI workflows within my development process.
✅ Prioritize local LLMs as the first choice to preserve data privacy and keep intellectual property inside the development environment. Cloud AI (ChatGPT, Claude) is used only as a last resort and only with the client’s permission.
✅ Running local LLM models provides flexibility in selecting the most appropriate model (e.g., Qwen‑3 Coder, Llama, IBM Granite) for tasks such as debugging code, generating boilerplate, or performing code reviews.
You, the client(s)
✅ High client‑retention rate (80 %+); clients keep coming back!
✅ Experience on $50k‑plus projects, though I also enjoy smaller, intellectually stimulating assignments.
✅ More than just “fingers and hands that punch code.”
✅ I plan my schedule in alignment with your needs.
Course and licences by IBM
- Deep Learning and Reinforcement Learning. Certificate number: S7Z8ZA6VPDJD can be verified in the Licenses section. Skills gained: Artificial Intelligence, Artificial Neural Networks, Convolution Neural Networks, Generative Model Architectures, Generative AI, Machine Learning Methods, Computer Vision, Model Optimization, Machine Learning, Transfer Learning, Unsupervised Learning
Selected client feedback
“…works well independently, brings new insights and polished solutions, responsive and clear with top‑quality work. Have already hired again!”
“We knew we would need a highly organized and innovative developer who could self‑manage the development process, and Theo delivered.”
“Excellent work – understood the task well, provided good feedback, completed work within schedule.”
“Provided a very straightforward and well‑thought‑out plan.”
“Theo would be the best choice.”
If you are interested or need more information, let me know.
Theo
Swift
AI Mobile App Development
iOS Development
iOS
Python
In-App Purchases
Core Data
iPadOS
UIKit
Core Bluetooth
Objective-C
AI Model Development
Apple HealthKit
SwiftUI
Core Graphics
Core Location
AI Model Training
Machine Learning
Muhammad Ahsun A.
London, United Kingdom
$15/hr
5.0
2 jobs
⚡ I build production-ready, AI-powered web applications — from model training to fully deployed web products.
With 7+ years of hands-on experience across full-stack development and AI/ML engineering, I specialize in one thing most developers can't offer: the full picture. I don't just integrate an API and call it "AI" — I architect robust, scalable systems where the AI layer genuinely solves your business problem.
If you need a freelancer who can handle the entire stack — AI/ML backend, REST APIs, and polished frontend — you've found your person.
What I build for clients:
✅ ML model development, fine-tuning & deployment (PyTorch, TensorFlow and more)
✅ LLM API Integration. GPT, Claude, Gemini integration into existing SaaS, CRMs, ERP & Web apps
✅ RAG systems — "chat with your documents" (PDFs, databases, wikis)
✅ AI agents & autonomous workflow automation (LangChain, CrewAI, LangGraph
✅ Custom AI chatbots & LLM-powered apps (GPT, Claude, Gemini, Llama)
✅ Full stack web applications (React/Next.js + Python/FastAPI/Django)
✅ Data pipelines, annotation systems & MLOps infrastructure
✅ Cloud deployment AWS, Google Cloud, Azure, Digital and many more
⚙️ Tech Stack at a glance:
→ AI/ML: Python · PyTorch · TensorFlow · Scikit-learn · HuggingFace · OpenAI API · Anthropic API
→ LLM Frameworks: LangChain · LlamaIndex · LangGraph · CrewAI
→ Vector DBs: Pinecone · Weaviate · ChromaDB · FAISS
→ Backend: FastAPI · Django · Node.js · PostgreSQL · MongoDB
→ Frontend: React · Next.js · TypeScript · Tailwind CSS
→ Cloud/MLOps: AWS · GCP · Docker · GitHub Actions · SageMaker
💡 Why Clients Choose Me:
Most ML engineers can't build a polished, deployable product.
Most full-stack developers don't truly understand AI systems.
I bridge both worlds — and I've done it for 7+ years.
You get a developer who:
→ Understands your business problem first, code second
→ Delivers working systems, not just demos or prototypes
→ Communicates clearly throughout — no technical black boxes
→ Has seen enough projects to know what breaks in production
I work with startups, SMBs, and enterprise teams across the US, UK, EU, and Middle East. Whether it's a greenfield AI product or adding intelligence to your existing platform, I bring the same rigorous engineering approach.
I focus on outcomes that matter: systems that save you time, reduce costs, or generate revenue.
📩 Message me with your project details — let's build something great together.
#FullStackDeveloper #MERNStack #AIDevelopment #OpenAI #AIChatbot #Automation #Microservices #AWS #ML Engineer
AI App Development
AI Bot
API Development
Artificial Intelligence
Machine Learning
Deep Learning
AI Chatbot
AI Agent Development
AI Development
AI Model Integration
Large Language Model
Natural Language Processing
Data Science
Python
FastAPI
LLM Prompt Engineering
Chatbot Development
LangChain
Amazon Web Services
Full-Stack Development
Abiodun A.
Lincoln, United Kingdom
$5/hr
5.0
8 jobs
Are you feeling overwhelmed by your GoHighLevel setup confused, incomplete, or not delivering the results you expected?
Looking for a GoHighLevel expert who goes beyond basic page building to create a complete, results-driven system?
You’re in the right place.
I specialize in helping business owners, coaches, consultants, agencies, and service-based brands build powerful, conversion-focused systems within GoHighLevel. My approach goes beyond simple setups I design fully integrated systems that capture leads, automate follow-ups, schedule appointments, nurture prospects, and elevate your overall client experience.
This isn’t just about setting things up.
I build GoHighLevel systems that are strategic, scalable, and tailored to how your business actually operates helping you save time, reduce manual work, and drive consistent growth.
My services include:
✅ GoHighLevel account setup
✅Gohighlevel sales funnel
✅Gohighlevel landing page
✅ Gohighlevel Website
✅Gohighlevel workflow
✅Go high level funnel
✅Gohighlevel SEO
✅Gohighlevel calendar
✅Go high level email automation
✅Convert clickfunnels landing page to gohighlevel
✅Triggers and workflow
✅Gohighlevel campaigns
✅Lead generation funnels
✅ Form/Survey
✅CRM Management
✅Zapier Integration
✅Email Marketing
✅Integrate payment solutions such as Stripe.
✅GHL Automating Onboarding Processes
✅Checkout Pages
✅Mailgun Integration, Zapier Integration, and Twilio Integration
✅GoHighLevel AI Agents
I've worked with businesses across various industries, from e-commerce and B2B to non-profit and healthcare.
I handle full project management from start to finish, ensuring your websites drive results. Regular communication is important to me, so let’s keep in touch and grow your business together! 🚀
𝗞𝗲𝘆𝘄𝗼𝗿𝗱𝘀:
GoHighLevel automation expert,GoHighLevel Sales Funnel Experts, gohighlevel (GHL) Subaccount, GoHighLevel Website Design, GoHighLevel Landing Page, GoHighLevel Sales Funnel Creation, GoHighLevel Automation, GoHighLevel SaaS Configuration, GoHighLevel Email Marketing, GoHighLevel Calendar Setup, GoHighLevel Appointment and Opportunity Management, GoHighLevel Integrations, GoHighLevel Workflow Design, GoHighLevel Designing WordPress Templates in GHL, GoHighLevel Snapshot Creation and Setup, GoHighLevel Email Configuration, GoHighLevel Community Setup, GoHighLevel Membership Setup, GoHighLevel Store Design, GoHighLevel Sales funnel design, GoHighLevel Landing page, GoHighLevel Landing page design, GoHighLevel CRM Automation, GoHighLevel Website, GoHighLevel Sales funnel Implementation, GoHighLevel Website, GoHighLevel CRM Software, GoHighLevel Email Marketing, GoHighLevel Email Automation, GoHighLevel Email Campaign, GoHighLevel Email Campaign Setup, GHL AI Agents
GoHighLevel automation expert,GoHighLevel Sales Funnel Experts, gohighlevel (GHL) Subaccount, GoHighLevel Website Design, GoHighLevel Landing Page, GoHighLevel Sales Funnel Creation, GoHighLevel Automation, GoHighLevel SaaS Configuration, GoHighLevel Email Marketing, GoHighLevel Calendar Setup, GoHighLevel Appointment and Opportunity Management, GoHighLevel Integrations, GoHighLevel Workflow Design, GoHighLevel Designing WordPress Templates in GHL, GoHighLevel Snapshot Creation and Setup, GoHighLevel Email Configuration, GoHighLevel Community Setup, GoHighLevel Membership Setup, GoHighLevel Store Design, GoHighLevel Sales funnels, GoHighLevel, GoHighLevel Expert, GHL Expert, HighLevel Specialist, GoHighLevel Setup, GHL Setup, GoHighLevel Automation, HighLevel Automation, GoHighLevel CRM, GHL CRM, GoHighLevel Funnel, Funnel Builder, Sales Funnel, High Converting Funnel, Landing Page Design, Funnel Optimization, GoHighLevel Website, Website Builder, Responsive Website Design, Conversion Optimization, Lead Generation, Lead Capture, Lead Nurturing, Email Marketing, SMS Marketing, Automation Workflow, Workflow Automation, Marketing Automation, CRM Automation, Pipeline Setup, Sales Pipeline, Appointment Booking, Calendar Setup, Client Onboarding, Client Management, Customer Journey, Funnel Strategy, Digital Marketing Funnel, Conversion Funnel, ClickFunnels Alternative, Funnel Hacking, Lead Magnet Funnel, Webinar Funnel, Booking Funnel, Service Funnel, Coaching Funnel, Agency Funnel, SaaS Funnel, Local Business Funnel, AI Chatbot, AI Bot Setup, GHL AI Bot, Chatbot Automation, Messenger Bot, SMS Bot, Conversational AI, Customer Support Bot, Lead Qualification Bot, Automation Sequences, Drip Campaigns, Email Sequences, SMS Sequences, Follow-Up Automation, Trigger Automation, Campaign Setup, Marketing Campaign, CRM Organization, Contact Management, Tagging System, Segmentation, List Building, Audience Segmentation, Client Retention, Client Experience, Customer Experience, UX Optimization, UI Design, Website Redesign, Funnel Redesign, Conversion Rate Optimization, CRO Expert, A/B Testing, Split Testing, Analytics Tracking, Performance Optimization, Google Analytics Integration, Facebook Pixel Setup, GHL, GHL
HighLevel
CRM Automation
Marketing Automation
Automated Workflow
Sales Funnel Builder
Sales Funnel
Landing Page
Lead Generation
Lead Management Automation
CRM Software
Web Design
Social Media Marketing
Facebook
Customer Relationship Management
Marketing Strategy
Lead-Nurturing Email
Campaign Management
Marketing Strategy Report
Project Workflows
Automation
Muhammad M.
Leicester, United Kingdom
$10/hr
5.0
48 jobs
I have performed 6+ years of Mobile App Developer, Lead Generation, Data Entry and Web Research. I have extensive familiarity with Android And IOS development, MS Office (Word, Excel, Power Point), eBay searching,, and PDF Files conversion. I have completed a lot of Mobile Apps, Lead Generation, Web Research and PDF to Excel conversion projects. I have good communication skills, exceptional typing skills, and excellent grammar and spelling.
I am a Top Rated Freelancer 🥇🏆
25+ projects completed on Upwork
Contact me if you are looking for:
Android app, IOS app, ionic developer, flutter developer, Data Entry, Data Scrapping, Data mining, Data Collection, Web Research, Lead Generation, PDF to Excel conversion, Google Sheets, Email Collections, LinkedIn data collection.
I am also expert in Graphic Designing. I can create Thumbnail / NFT / Brochure, Poster & Flyer Design / Logo Design & Brand Identity / Business Cards, Envelopes / Print & Layout Design / Landing Page Design / Social Media Banners, Web Design, Background remover, Vector image, Photo Touchup, Logo Animation, video animations, UX/UI design, Video Editing etc.
Skills :
Adobe Photoshop, Adobe Illustrator, Adobe XD, Adobe InDesign, Adobe Premiere Pro, PowerPoint, Canvas, Corel Draw
I would be thrilled to have an opportunity to work with you.
Thanks
Product Listings
Data Entry
Microsoft Excel
Data Scraping
Mobile App Development
Graphic Design
Flutter
Android App Development
PDF Conversion
Administrative Support
Ionic Framework
Image Editing
Lead Generation
Data Extraction
Logo Design
Vinodkumar K.
London, United Kingdom
$30/hr
5.0
1 jobs
We help businesses transform their operations through powerful, scalable digital solutions combining development, automation, and strategy into one seamless system.
At Rishvi, we don’t just build websites or apps. We design and implement end-to-end business systems that streamline workflows, improve efficiency, and support sustainable growth.
Our core solutions include:
• Custom Website Development & E-commerce Platforms
• Odoo ERP Implementation & Advanced Customization
• CRM Systems & Business Process Automation
• E-Invoicing Solutions (UAE & UK -compliant & integrated systems )
• Mobile App Development (Android, iOS & Flutter)
• API Integrations & System Architecture
• SEO & Digital Growth Strategies
What makes us different:
We approach every project from a business perspective first ensuring that the technology we build directly impacts your operations, productivity, and revenue.
Instead of isolated services, we deliver connected systems that work together reducing manual work, improving visibility, and enabling smarter decision-making.
Who we work with:
• Growing businesses looking to automate operations
• Companies implementing ERP or CRM systems
• Organizations needing scalable digital infrastructure
• Clients seeking a long-term technology partner
If you're looking for more than just a freelancer and want a reliable digital partner who can design, build, and scale your systems we’d be glad to work with you.
Odoo
CRM Development
ERP Software
Web Development
Mobile App Development
Business Process Automation
SaaS Development
WordPress e-Commerce
Shopify
Linnworks
Macros
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