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Grammarly has become indispensable for millions of users, transforming how they write, communicate, and enhance their grammar and writing skills. The app provides advanced AI-powered grammar checks, writing style suggestions, and plagiarism detection to elevate users’ writing quality. However, building an app like Grammarly requires more than just a simple spell-checker—it involves sophisticated natural language processing (NLP) algorithms, real-time suggestions, and compliance with privacy laws for sensitive interactions.
Developing an app like Grammarly comes with its own complexities, such as enabling cross-platform compatibility (desktop, mobile, web browser extensions), integrating AI-based natural language processing, and ensuring compliance with data privacy laws like GDPR and CCPA. Because Grammarly also handles sensitive content through its document editing and live cloud suggestions, data encryption and secure user input processing become paramount development concerns.
Understanding these aspects is key to evaluating the full app development cost. In this article, we dive deep into the factors that influence costs when building a Grammarly-like app, reflecting on core software components, unique features, platform requirements, and security details needed to deliver a seamless and secure user experience in the U.S. market.
One of the major components driving app development cost is building an application that seamlessly works across multiple platforms and devices. Grammarly itself offers support for desktop apps, mobile applications, and browser extensions—making platform compatibility essential for your success.
For an app like Grammarly , developing for both iOS and Android is necessary to ensure maximum market reach in the U.S. Given that iOS caters to a more premium audience accustomed to seamless interfaces, developing a more polished iOS app is essential. On the other hand, the Android ecosystem is more widely used but fragmented, which requires additional testing and development time to ensure performance across the various Android devices and versions.
Beyond basic compatibility, adding premium features, such as real-time writing suggestions that integrate directly across multiple apps (e.g., note-taking apps, email clients, etc.), further complicates development. Ensuring synchronization between devices while maintaining low-latency performance increases both the development cost and complexity.
Explore Android App Development and iOS App Development.
You could choose cross-platform development tools like React Native or Flutter to reduce the development timeline and expense by sharing a single codebase across iOS and Android. However, with a Grammarly-like app, performance could prove to be a limiting factor since live grammar suggestions, real-time spell-check, and NLP algorithms demand high processing power and device-specific optimizations.
Additionally, compatibility with desktop platforms for Grammarly’s use in mainstream writing tools like Microsoft Word and Google Docs adds another layer of complexity, further increasing development costs. You'll need to develop desktop-specific versions to ensure smooth integration and live writing suggestions on desktops, similar to Grammarly’s desktop app.
At the basic level, a Grammarly-like app must include core functionalities aimed at providing grammar and spell-check solutions:
These basic functionalities would serve as the foundation of a writing assistant, but they don’t offer advanced corrections and feedback like punctuation, sentence restructuring, or style adjustments—features most U.S. users expect.
To remain competitive in the writing assistant market, your app must provide richer functionality, with more sophisticated algorithms for understanding context and providing detailed writing feedback. Intermediate features include:
These intermediate-level features involve more complex text processing and inline writing corrections. Integrating NLP capabilities with real-time, multi-platform content recommendations in various contexts (social media posts, formal emails, etc.) increases development time and back-end complexity.
Advanced features distinguish an app like Grammarly with highly intelligent and customizable writing guidance:
These advanced features require heavy investment in machine learning models, content review algorithms, and cloud-based storage that can process and retain these models for continuous user interaction. Implementing AI-based writing suggestions for complex documents and plagiarism detection involves significant resource allocation toward cloud architecture and real-time data processing, thereby elevating app development costs.
Developing an app like Grammarly means carefully crafting a balance between seamless design and powerful functionality. The user interface (UI) needs to feel intuitive, while the user experience (UX) should guide users toward optimizing their writing.
Writing assistant apps like Grammarly must blend seamlessly into a user’s writing environment without overwhelming them. U.S. users expect minimalism when interacting with productivity tools—meaning the app should suggest corrections or improvements without interrupting the user’s workflow.
Incorporating an in-line suggestion system that hovers non-intrusively over writing errors or potential improvements, while staying intuitive enough for quick action, raises design demands. Building these personalized corrections as dynamic overlays, integrated into existing apps like Google Docs or email clients, increases UX complexity—requiring more design attention and testing.
In the U.S., users are increasingly working across multiple devices—desktop, tablet, mobile. Your design should ensure consistency across these platforms, maintaining a sense of continuity in user experience. For example, a user who starts editing a document on their phone should be able to continue from where they left off on their desktop.
This requires investment in responsive design, ensuring all app features and corrections appear flawlessly on a variety of screen sizes without making the interface cluttered or slow. Every added UX/UI element, while improving the user experience, requires design and front-end development professionals to rigorously test and scale—driving up overall design costs.
Read about Responsive Design for Mobile First Success.
Grammarly’s seamless operation comes from its integration with numerous third-party systems, including cloud storage and external writing platforms. Developing these types of integrations can significantly impact development costs.
At the heart of an app like Grammarly are integrated natural language processing (NLP) APIs that help detect errors, identify correct language usage, and provide writing suggestions. Integrating sophisticated AI models (e.g., OpenAI or Google’s NLP services ) for semantic analysis, language correction, and contextual feedback involves advanced development expertise .
For cloud-based suggestions and providing users with the ability to access their personalized settings across multiple devices, your app needs to connect with cloud storage platforms like AWS, Google Cloud, or Microsoft Azure. Cloud storage is vital for real-time syncing, storing user settings, maintaining dictionaries, and offering backups through secure channels. Setting up cloud infrastructure optimized for multiple users results in higher overall costs.
Grammarly’s success lies in its seamless integration with existing productivity tools like Google Docs, Microsoft Office, and other word processors. For your app to compete, you’ll need integrations with these major software suites, which involves API development, testing, and adjusting for specific platform rules such as Microsoft Office’s Open XML standard.
These integrations offer enormous user value but significantly affect costs due to API maintenance and development work associated with popular cloud-based service providers.
The back-end architecture for a Grammarly-like app must handle real-time data processing and large-scale storage for both natural language data and user-generated content.
Processing live suggestions for spelling, grammar, sentence completion, and plagiarism detection across multiple platforms and devices requires a robust and scalable back-end infrastructure. To provide instant suggestions, the development team must implement real-time data syncing through low-latency APIs that transmit encrypted information rapidly. AWS Lambda, Google Cloud Functions, or Apache Kafka could be necessary to ensure optimal event-driven architectures.
Grammarly handles an enormous volume of sensitive information from its users. Documents edited by Grammarly users contain sensitive information, requiring strong encryption protocols and compliance with U.S. data laws like CCPA (California Consumer Privacy Act) and even HIPAA if the app extends into fields that handle medical documentation.
Additionally, user preferences, writing habits, and custom rules must be stored and securely retrieved. Cloud storage systems like Google Cloud Storage, AWS S3, or Azure Blob Storage are critical for accommodating large file sizes and keeping encrypted transcripts. These systems also allow scaling, which adjusts necessary backend specifications as traffic grows.
Building infrastructure capable of processing large volumes of incoming text, managing huge datasets, and storing encrypted logs raises costs exponentially, but is critical for ensuring scalability and security.
Once your Grammarly-like app has been launched, ongoing maintenance and updates are vital to keeping it relevant, secure, and competitive within an evolving U.S. market.
AI and NLP models continually evolve, and your writing assistant must stay ahead of the curve. This involves frequent updates to the grammar rules, AI algorithms, and writing suggestions, all of which necessitate constant optimization. New trends in writing, dictionary updates, or even slang emergence must be reflected in real-time.
As features expand, there will inevitably be bug fixes and UI enhancements required. Frequent A/B tests, implementing new writing templates, and adding new integrations all require steady ongoing development to fit U.S. content creation trends. Regular audits of performance and bug detection will need constant investment in post-launch development.
These factors increase the long-term cost of maintaining and upgrading your application to meet evolving user expectations set by competitive apps like Grammarly.
The expertise of your development team plays a huge role in determining the cost of your Grammarly-like app.
Hiring U.S.-based development teams ensures a better understanding of the English language nuances , leveraging expertise in AI development (especially for English speakers). Additionally, given U.S.-based developers' familiarity with local compliance laws (like CCPA), they serve as an invaluable resource for ensuring privacy protection efforts are met from the ground up. However, their rates are typically higher, ranging between $150 - $250 per hour, which will naturally increase your overall cost.
Alternatively, you could opt for an offshore team based in regions like Eastern Europe, India, or Southeast Asia, which typically charge between $30 - $70 per hour. Although reduced in cost, overseeing time zone differences or potential language challenges may slow workflow. For highly complex NLP or AI-driven applications like Grammarly, you may often require a blended model, with core project management and strategy local to the U.S. and development outsourced offshore.
Given that Grammarly interacts with user input in real-time, stringent quality assurance (QA) testing becomes mandatory. The app would need to undergo rigorous functional testing, load performance evaluation, and ensure all grammar checks are accurate across varying writing contexts. Regression testing must ensure every new feature or update integrates smoothly with previous functionalities.
Both Apple's App Store and Google Play Store charge developer fees, as well as a commission on in-app purchases or premium subscriptions (typically up to 30% of revenue). You must allocate funds to ensure your app remains compliant with the guidelines set by these app stores.
Your app might store and process a large amount of written content. Therefore, compliance with privacy laws like GDPR in Europe and CCPA in California is important. Legal consultations, data security experts, and compliance measures drive the cost higher but are crucial for avoiding data breaches and ensuring users' privacy rights are protected.
Building an app like Grammarly involves integrating machine learning, natural language processing (NLP), and real-time suggestions across multiple platforms—a far more complex app category than general communication or productivity apps. Developing for a writing assistant requires top-tier NLP algorithms, compliance with English language rules, and contextual AI-based prompts.
For the U.S. market, where content creation tools are highly prevalent across industries like business, education, and creative writing, the demand for real-time editing tools is at an all-time high. Users expect top-tier recommendations for grammar, tone, and even plagiarism protection.
Building a Grammarly-like app necessitates a highly specialized skill set, including AI & machine learning expertise, creating in-depth text-analysis pullbacks, and maintaining reliable cloud infrastructure for processing these recommendations in real-time across multiple platforms.
At Scrums.com, we specialize in custom applications like Grammarly, equipped with AI-powered writing tools and contextual editing. Reach out for a custom development estimate and let’s turn your app idea into reality today!