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I will develop ai saas platform fintech medtech cybersecurity web
Marcin Walczyk
Vetted Pro
Top Rated
5.0
5.0
What people loved about this freelancer
iamstratos
Germany
Awesome results! Marcin with his team showed exceptional expertise in mobile app payments and marketing integrations. Thanks to completing this milestone, I'm...
darianjames
United States
I would highly recommend this mobile app development agency to anyone looking for top-notch development work, especially in the area of in-app purchases.
paul_foster
Argentina
I'm glad we've found Marcin's company. He suggested doing a project discovery stage, which was very detailed and successful. We changed our plans after Marcin's...
Vetted by Fiverr Pro
Marcin Walczyk was selected by the Fiverr Pro team for their expertise.
About this gig
At Inventively LLC, we build high-stakes, end-to-end apps for web, mobile, AI, and hardware. With 10+ years of expertise, we help entrepreneurs and organizations turn ideas into scalable, revenue-driving products.
Our projects typically range from $20k to $100k and run 1 to 5 months. We cover the full cycle: product workshops, UI/UX design, scalable architecture, development, and long-term support. Clients have achieved over $2,000,000 per year in in-app purchases under our guidance.
We are an official RevenueCat technology partner, a San Francisco company valued at $500M with $100M+ raised, powering over $8B in annual transactions. This gives our clients proven subscription monetization and growth strategies.
We specialize in profitable software businesses that last. Mobile and web apps, AI solutions, hardware integrations, payments and cloud systems, and reliable maintenance.
Kindly contact me: Contact seller -> Ask a question.
Get to know Marcin Walczyk
Marcin Walczyk
Vetted Pro
We build profitable software businesses: Marcin, CEO Inventively LLC
Top Rated
Marcin Walczyk is part of the Fiverr Pro catalog and has been hand-picked by a dedicated Fiverr Pro team for their skills and expertise.
Vetted for
Mobile App Development
Mobile App Maintenance
- FromUnited States
- Member sinceFeb 2019
- Avg. response time4 hours
- Last delivery3 weeks
Languages
English
Build scalable mobile, web, AI, and computer vision apps with a top-tier engineering team at your side. Leverage our expertise in development, design, payments, and marketing integrations.
As an official RevenueCat technology partner, a San Francisco-based startup that has raised over $100 million in funding, is valued at $500 million, and powers a platform processing over $8 billion annually, we're ready to help you achieve great success.
We build long-term partnerships with entrepreneurs who need a reliable tech team to deliver and maintain the software behind their growing business.
My Portfolio
FAQ
What does it mean that you are a RevenueCat tech partner?
As a certified RevenueCat Expert, we were selected by RevenueCat for our proven results and expertise in subscription optimization. This partnership enables us to leverage advanced tools and strategies, ensuring your app’s subscription model is optimized for maximum growth and revenue.
Do you take on small RevenueCat fixes or basic RevenueCat setup work?
As an agency, we focus on comprehensive app development and growth projects. While we do work with RevenueCat, we don't take on small fixes or basic setups. Our expertise is best utilized when we're involved in full-scale app development, where we can deliver the most impact and long-term success.
Can you sign in an NDA? ( Non-disclosure agreement )
Absolutely. We value confidentiality. I encourage NDAs and can use yours or provide our template. Rest assured, only essential team members access your data, ensuring your project's security and peace of mind.
By working with Inventively LLC will I get direct contact with Marcin?
Yes, by working with Inventively, you'll have direct contact with Marcin. His unique expertise in transforming app businesses into profitable entities ensures your project receives the best guidance. We take on a limited number of projects, ensuring you get the dedicated focus you deserve.
Do you provide support and maintenance after development and launch?
Yes, we provide ongoing support and maintenance to ensure your app's success and scalability. Our goal is to build lasting partnerships, offering continuous improvements, updates, and dedicated issue resolution to keep your app at the forefront.
What kind of access and control will I have over my project during development?
As our client, you will have real-time access to project progress, budget management, and goal status, ensuring full transparency and control at every step.
Do I have ownership of my mobile application, including the code?
Yes, you are the owner of Intellectual Property rights at all times.
Will you assist me in uploading my Android app to the Google Play Store? / my iOS app to the Apple Store? How?
Yes, of course. We will upload your Android application to the Google Play Store and your iOS app to Apple Store. It is also a part of our app development process. We will also guide you through the app setup on the stores regarding the marketing materials and descriptions.
Reviews
7 reviews for this Gig
| (7) | ||
| (0) | ||
| (0) | ||
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Rating Breakdown
- Seller communication level
- Recommend to a friend
- Service as described
Sort By
Most relevant
N newaiapp
United States
Excellent team with superb communication skills. Quickly fixed our mobile payment issues. Thank you!
$100-$200
Price
10 days
Duration
Helpful?P 
paul_foster
Repeat Client
Argentina
I'm glad we've found Marcin's company. He suggested doing a project discovery stage, which was very detailed and successful. We changed our plans after Marcin's feedback. His industry expertise is invaluable! This is much different than our past experiences with other development companies, which seem...
Helpful?D 
darianjames
Repeat Client
United States
I would highly recommend this mobile app development agency to anyone looking for top-notch development work, especially in the area of in-app purchases.
Helpful?M 
menus4all
Repeat Client
United States
So great working with Marvin. So very helpful. He got our project back on track.
Helpful?I 
iamstratos
Germany
Awesome results! Marcin with his team showed exceptional expertise in mobile app payments and marketing integrations. Thanks to completing this milestone, I'm confident that my marketing spending will lead to a further increase in the app's revenue. The new analytics data will help us be more efficient with app marketing.
Helpful?
Reviews
7 reviews for this Gig
| (7) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Recommend to a friend
- Service as described
Sort By
Most relevant
N newaiapp
United States
Excellent team with superb communication skills. Quickly fixed our mobile payment issues. Thank you!
$100-$200
Price
10 days
Duration
Helpful?P paul_foster
Repeat Client
Argentina
I'm glad we've found Marcin's company. He suggested doing a project discovery stage, which was very detailed and successful. We changed our plans after Marcin's feedback. His industry expertise is invaluable! This is much different than our past experiences with other development companies, which seem...
Helpful?D darianjames
Repeat Client
United States
I would highly recommend this mobile app development agency to anyone looking for top-notch development work, especially in the area of in-app purchases.
Helpful?M menus4all
Repeat Client
United States
So great working with Marvin. So very helpful. He got our project back on track.
Helpful?I iamstratos
Germany
Awesome results! Marcin with his team showed exceptional expertise in mobile app payments and marketing integrations. Thanks to completing this milestone, I'm confident that my marketing spending will lead to a further increase in the app's revenue. The new analytics data will help us be more efficient with app marketing.
Helpful?
