Writing Apps

Let’s craft the perfect writing app

Flexum helps you build exceptional editor applications that enable users to create, collaborate and communicate while enjoying a delightful experience.

Build bleeding-edge features

From drag-and-drop to AI-powered content generation, we can help you add features that enhance engagement with your app.

Slash commands

Enable intuitive slash commands, similar to Notion and Slack. Let users type a slash and keyword to quickly insert elements such as tables and images.

Drag and drop

Easily rearrange and organize content with an intuitive click-and-drag feature. Create a streamlined and user-friendly editing experience like Notion or Craft.

Real-time collaboration

Collaborate seamlessly with multiple users on a single document. Allow instant edits, feedback, comments and suggestions, just like Google Docs or Quip.

Voice typing

Convert spoken words into text using speech recognition technology. Make the content creation process more efficient, just like Google Docs or Word.

AI integration

Use AI to reimagine the content creation experience. We build apps with predictive text, grammar, style, and generative content, just like Notion or Grammarly.

Sketching and painting

Incorporate hand-drawn illustrations, diagrams, or annotations directly into your documents, just like Microsoft OneNote or Evernote.

We’ll build your editor app using a proven framework

The right framework can make or break your app. We know them all, inside and out and trust these powerful frameworks to create a dynamic experience that your users will love.

TipTap logo


A customizable framework for building rich text editors with a modular architecture and flexible API.

Quill logo


A powerful and flexible WYSIWYG editor framework with a modular architecture that makes it easy to customize.

Draft.js logo


A framework developed by Facebook that provides a set of primitives for building rich text editors in React.

TinyMCE logo


A popular open-source framework for building WYSIWYG editors with a simple API and a wide range of plugins.

CKEditor logo

CKEditor 5

A customizable and scalable framework for building advanced and intuitive editors with a modular architecture.

ProseMirror logo


A toolkit for building rich-text editors with a custom document model and support for collaborative editing.

Slate logo


A flexible and customizable framework for building custom editors with a modular architecture and a flexible API.

Lexical logo


A modern and lightweight framework for building custom text editors with a focus on performance and simplicity.

Case studies

Discover how we helped a visionary startup build an AI-powered writing app

“Flexum exceeded expectations over and over, and even introduced functionality that we had not considered.”

Transparency is a core value

Forget custom quotes, long-winded proposals and gotcha pricing schemes. Let’s start the relationship off on the right foot with transparency and clarity.

Starting at
per month with
a 3-month commitment
  • Accelerated design sprints
    Whether you’re starting a new business or accelerating your roadmap, we believe success starts with a rapid, design-led phase to define the scope and long-term success.
  • Interactive, clickable prototype
    We aim to ship an interactive, clickable prototype within a few weeks. We also use the prototype to clarify the scope for the MVP and help capture the long-term opportunity.
  • Landing page development
    As part of the MVP, we’ll help you design and develop a landing page to gauge early interest and feedback.
  • Technical architecture
    While your product and designs come into focus, we’ll start planning a scalable, forward-looking technical architecture that gets you to the MVP stage and far beyond.
  • MVP launch (scope TBD)
    At the end of the 3-month MVP cycle, we’ll aim to launch a lean, functional version of your product. The scope of functionality depends on all the work we’ll do during the initial design and planning sprints.
  • Full-stack, dedicated teams:
    You’ll work with a dedicated group of designers and engineers focused on the rapid, design-led development of your MVP.
    1 full-stack engineer
    1 product designer
    1 architect (part-time)
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Questions? We’ve got answers.

These are some of the most frequently asked questions. If you can’t find the answer you’re looking for, let’s connect.

How do I get started working with Flexum?

The first step is to get in touch and jump on an intro call with our founders Myron and Anton. Typically, we’ll start a 1-2 day spike to design or build something small, but meaningful, to make sure we’re a good fit for each other.

What makes Flexum different?

Flexum is a boutique product agency that’s laser-focused on helping entrepreneurs and intrapreneurs build winning products. We do so with a design-led process, transparent pricing, and a drive to add value from day one. At core, we’re entrepreneurs like you and know what it takes to build differentiated products and find product/market fit.

How do you charge for your services?

Our pricing is transparent, check out our pricing page to learn more. To sum it up, our goal is to “productize” our services entirely to bring a level of predictability and consistency that the agency world has been missing.

How are projects managed?

Every customer has a dedicated contact person and the founders are also always involved. We’re a boutique agency so you get a lot of personal attention. We use a variety of products to help manage progress and knowledge, but we’re not religious about the choice of tools. We’re happy to adapt to your preferences, but will suggest a few of our defaults at the outset.

How quickly can I scale a team?

It depends. We always have capacity to onboard new clients and extend teams. If you’re looking to get started, build great products and step on the gas when we find product/market fit, then we’re the right fit. However, if you need to build a team of 3 designers and 12 engineers yesterday, we can help, but it’ll take time.

Get in touch

Ready to take your editor application to the next level?

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