We launch Startups
and create
amazing Products

We collaborate on world-class projects that revolutionize industries and occasionally transform lives. That is our philosophy — crafting exceptional products that make a difference.
Web Apps
Mobile Apps
4xxi: Startup Launcher

Days to start


Raised by our clients


years of experience

Inspiring Success Stories

Innovating Wealth Management


Transforming Law School Study


Redefining Incident Management


Transforming Running Experience


How we work?

Step 1: Research & Development

We thoroughly assess your idea, analyze competitors, and identify core differentiators. Our team designs a comprehensive list of features to ensure your product stands out in the market.

Step 2: Planning & Design

We create a core roadmap and user flows for your project. Our experts collaborate with you to understand your vision and translate it into a well-defined plan, ensuring a smooth development process.

Step 3: Development

Our small, but skilled team brings your idea to life by developing a minimal viable product. We find a balance between functionality, usability, and scalability to deliver a high-quality product that meets the idea.

Step 4: Launch

We handle the entire process of packaging your product for a successful launch. From optimizing performance to ensuring a seamless user experience, we make sure your product is ready to make a strong impact in the market.


Step 5: Presentation

We assist you in effectively presenting your product to potential investors, stakeholders, or customers. Our team helps you craft compelling pitches and demonstrations that showcase the unique value of your offering.

Step 6: Transfer or Maintenance

After launch, we offer options to either transfer the project to your team (and help you to build one if necessary) or provide ongoing maintenance and support. We ensure a smooth transition or provide reliable maintenance services to keep your product running smoothly.


Why work with us?

  • 1

    Experienced and Cohesive Team

    Our small and focused team has been working together for over 10 years, bringing a wealth of experience and a seamless collaboration that ensures exceptional results for your project.

  • 2

    Rapid Development

    We understand the importance of speed without compromising quality. Our agile approach allows us to deliver your web and mobile app projects swiftly, ensuring quick market entry and a competitive edge.

  • 3

    Comprehensive Expertise

    With our all-in-one approach, we provide expertise in development, marketing, and sales. From crafting exceptional code to implementing effective marketing strategies and driving sales, we offer a holistic solution for your startup's success.

They write about the projects we have built

What Our Clients say?

They take what they do seriously, doing things well so they can be proud of the work. Based on our 5 years of experience together, they’ve always taken the product as a challenge. They brought ideas and asked why we wanted to do it in a certain way. If I were building a new product, I would definitely get their feedback since I respect their opinion a lot. They are generally a good team to work with. ... They builds software to their own quality standards, which are high even compared to Silicon Valley.

Review by Sergey Fedorov
Sergey Fedorov
Director of Product, AnchorFree

Working with the team has been one of the best commercial experiences of my business life.

Review by Steven Emanuel
Steven Emanuel
President, Emanuel Quant Services

They did a great job. The biggest challenge for me when outsourcing, was that I was outsourcing. 4xxi is not an in-house team, but they were phenomenal. I definitely needed people who could help 4xxi understand what’s going on, but there was never a question of them not being able to deliver against what was being put in front of them.

Review by Gayle Meyers
Gayle Meyers
CEO, IndustryIndex

I’ve been working with them for 15 years. I’ve known them for a long time. ... I haven’t given them a project yet that they couldn’t handle… they’ve always delivered.

Review by David Nadezhdin
David Nadezhdin
Founder, Circus Intersection

Their passion, their energy, and their youthfulness impress me. Their management and leadership are senior, which is a good thing, but the development team is composed of younger, hipper, smarter, cutting-edge application users who are able to transfer ideas from cool apps and implement those ideas.

Review by Michael Sher
Michael Sher
CEO, GroupDoLists

I’ve been very happy with 4xxi. They deliver on time. So far, new and complex features are delivered according to our specifications.

Review by Trivago Team
Trivago Team
Product manager, Trivago

They are a fantastic team and we wouldn't be where we are today without them!

Review by Josh Lewis
Josh Lewis
Director & Co-Founder, Challenge Social

They have confidence in the IT, education, and financial area, which is impressive. It’s been a really good relationship so far, and we consider them partners.

Review by Konstantin Seregin
Konstantin Seregin
Manager of Digital Projects, Smart School

It has been a pleasure to work with 4xxi, they are a great partner. They deliver on every aspect they say they are going to. I already have a great site, but it’s about to get so much better. ... What I do love about working with them is that they don't just take the words that we say and implement them, or the functionality that we want and implement it. They are great at giving their feedback from their experience of what they see works and doesn't work. So they're almost a part of our team as far as helping our business to grow and evolve.

Review by Mara Landis
Mara Landis
Founder, NutmegAspirin