7 Best Tools for Mainframe Application Modernization in 2026 | Adalo

Mainframe modernization remains one of enterprise IT's most pressing challenges in 2026, with billions of lines of COBOL still powering mission-critical operations. This guide covers the seven best tools for transforming legacy systems into modern, accessible applications.

While most tools focus on backend transformation—converting code or exposing APIs—the frontend layer often determines modernization success. One powerful approach is building modern interfaces with Adalo—a no-code app builder for database-driven web apps and native iOS and Android apps, one version across all three platforms, published to the Apple App Store and Google Play—that connects to REST APIs exposed by your modernized mainframe services.

From AI-powered code transformation to rapid mobile development, these tools help you launch modernized applications faster, reach broader audiences through app store distribution, and deliver the push notification capabilities today's users expect.

When evaluating mainframe modernization tools, the choice ultimately depends on your modernization strategy and whether you're focusing on complete migration, API integration, or modern frontend development. While traditional platforms handle core mainframe transformation, Adalo can rapidly build mobile and web interfaces that consume REST APIs exposed by modernized mainframe services. This comprehensive guide examines the top mainframe modernization tools, with particular emphasis on how Adalo accelerates the critical frontend modernization phase.

Key Takeaways

• Adalo enables rapid frontend modernization with drag-and-drop mobile/web app building, creating modern interfaces for mainframe data in weeks
• AWS Mainframe Modernization provides AI-powered COBOL transformation at $0.103 per line of code after 120,000 free lines
• IBM z/OS Connect exposes CICS, IMS, MQ (via MQ Service Provider), and Db2 as REST/JSON services for API enablement
• Mainframe modernization market projected to reach $86.14 billion by 2031, per The Insight Partners
• Organizations report $25 million average annual savings from modernization, according to Kyndryl's 2026 survey
• Adalo pricing starts at $45/month (Starter plan), with Professional at $65, Team at $200, and Business at $250 monthly
• External Collections (REST/JSON only, no GraphQL/XML) available on Professional plans and higher

Understanding mainframe modernization in 2026

Mainframe modernization represents one of the most critical challenges facing enterprises today. While insurance companies spend approximately 70% of IT budgets on legacy system maintenance, and 56% of mission-critical applications still run on mainframes, according to Kyndryl's 2026 research, organizations urgently need transformation strategies. The modernization market is experiencing explosive growth, expanding from $21.5 billion in 2026 to a projected $76.16 billion by 2032 at a 15.1% CAGR per Credence Research.

Three primary modernization approaches dominate the landscape:

• Replatforming - Often completed in 6-12 months, can achieve significant infrastructure cost reduction
• Refactoring - Typically 12-24 month timeline, transforming COBOL to modern languages
• Rebuilding - Usually 24-48 months for complete architectural overhaul with microservices architecture

According to Kyndryl's 2026 survey, 96% of organizations plan to move workloads, with an average of 36% to be migrated, while their 2026 survey shows approximately $25 million in average annual savings. The key to success lies in selecting the right combination of tools for each phase of transformation, as detailed in modernization strategy guides.

Top mainframe modernization tools ranked

1. Adalo: Rapid frontend development for modernized services

Adalo accelerates the frontend modernization phase by enabling rapid development of mobile and web applications that connect to modernized mainframe services. Adalo states it serves over 2 million end users across published apps, demonstrating its production-ready capabilities.

Key Adalo Capabilities for Modernization:

• Visual development - Build interfaces without coding using drag-and-drop components
• App store publishing - Direct deployment to iOS App Store and Google Play Store
• External Collections - Connect to REST/JSON APIs (Professional plan and higher required) - no GraphQL/XML support
• Adalo API - CRUD access to your app's data (Team & Business plans only)
• Component marketplace - Pre-built integrations for payments, analytics, and data visualization
• Rate limits - The Adalo API is rate-limited to 5 requests/second; External Collections are also rate-limited

Modernization Use Cases:

Adalo works well when organizations need to modernize customer-facing interfaces while backend transformation continues quickly. The platform's component marketplace provides ready-made integrations for presenting mainframe data in modern formats.

For financial services modernizing core banking systems, Adalo enables deployment of mobile banking apps that connect to API-exposed mainframe services. Retail companies leverage Adalo's e-commerce capabilities to modernize inventory interfaces. Note that for regulated workloads with PHI, organizations should use HIPAA-eligible platforms with BAA support.

Current Pricing Structure (Monthly):

• Starter - $45/month (or $36 billed annually)
• Professional - $65/month (or $52 annually) - includes External Collections
• Team - $200/month (or $160 annually) - includes Adalo API access
• Business - $250/month (or $200 annually) - includes Adalo API access

Visit Adalo's pricing page for current plan details, app action limits, and editor restrictions. The transparent pricing model provides predictable costs compared to usage-based enterprise platforms, as explored in our pricing comparison guide.

2. AWS Mainframe Modernization

Amazon Web Services offers comprehensive cloud-based modernization with AI-powered transformation tools. AWS Blu Age Automated Refactor uses machine learning to analyze mainframe code patterns and generate cloud-native equivalents.

Key AWS Capabilities:

• Automated COBOL transformation - $0.103 per line of code after 120,000 LOC free tier
• Managed runtime environments - Priced per vCPU-hour with auto-scaling (AWS M2 pricing)
• AWS Transform - Currently offers core assessment & transformation features at no cost to AWS customers (AWS Transform)
• Comprehensive migration patterns for rehosting, refactoring, and rebuilding

AWS excels at complete mainframe migration to cloud infrastructure. The platform's strength lies in comprehensive transformation capabilities, though costs can escalate for large-scale migrations, as discussed in cloud migration strategies.

3. IBM z/OS Connect

IBM's modernization suite provides sophisticated tools for organizations maintaining hybrid mainframe operations. IBM z/OS Connect exposes CICS, IMS, MQ (via MQ Service Provider), and Db2 as REST/OpenAPI services with JSON support, bridging legacy and modern systems.

IBM Modernization Features:

• z/OS Connect - API-enables mainframe applications without code changes
• watsonx Code Assistant for Z - Supports COBOL understanding and Java transformation
• Z DevOps portfolio for continuous integration
• Real-time data streaming through IBM Z Digital Integration Hub
• MSU-based pricing model for mainframe software

IBM's approach suits organizations requiring gradual modernization while maintaining mainframe operations. The platform ensures compatibility with existing systems through deep mainframe expertise, as analyzed in enterprise platform comparisons.

4. Google Cloud Mainframe Modernization

Google Cloud leverages AI through its Mainframe Rewrite service powered by Gemini (currently in Preview). The platform emphasizes automated discovery and migration planning.

Google Cloud Strengths:

• Dual Run technology for parallel validation (online transactions in Preview)
• Mainframe Rewrite (Gemini) - AI-assisted code transformation (Preview)
• Migration Assessment Tool (MAT) for automated discovery
• BigQuery integration for data modernization
• Comprehensive migration factory approach

Google Cloud excels at data-centric modernization, particularly for organizations seeking to leverage advanced analytics on mainframe data, similar to approaches in modern app development.

5. Microsoft Azure Mainframe Migration

Microsoft's approach combines Azure services with partner solutions. Logic Apps provide orchestration while Host Integration Server technologies bridge legacy systems through documented connectors for IBM MQ, CICS, IMS, DB2, and 3270.

Azure Modernization Tools:

• Logic Apps for workflow orchestration
• Host Integration Server for mainframe connectivity (CICS/IMS/MQ/DB2/3270)
• Partner ecosystem, including Micro Focus and Asysco
• Azure DevOps integration for CI/CD
• Azure Arc for hybrid connectivity

Azure suits organizations invested in Microsoft technologies, offering seamless integration with existing infrastructure as detailed in enterprise app building guides.

6. OutSystems

OutSystems provides a low-code platform designed for enterprise modernization, enabling the gradual replacement of mainframe components while maintaining business continuity.

OutSystems Capabilities:

• Visual development with enterprise features
• Legacy system integration via comprehensive connectors
• API layer support for gradual modernization
• Documented case studies, including MicroMain's legacy rewrite with multilingual support added in one month
• Custom enterprise pricing (contact for quotes)

OutSystems demonstrates proven success in mainframe modernization projects through vendor case studies, as explored in low-code platform comparisons.

7. Mendix

Siemens-owned Mendix has been recognized as a Leader in Gartner's Magic Quadrant for Enterprise Low-Code platforms for nine consecutive years (as of 2026) according to Mendix.

Mendix Features:

• Model-driven development for rapid application creation
• Enterprise integration capabilities
• Cloud-native architecture with containerization
• AI-assisted development tools
• Pricing varies - Standard tier approximately $998/month (Mendix pricing)

Mendix excels at building new applications that integrate with modernized mainframe services, particularly for organizations requiring regulatory compliance, as discussed in enterprise development strategies.

Why Adalo excels for frontend modernization

While comprehensive mainframe transformation requires specialized platforms, Adalo effectively addresses the critical frontend modernization phase. Adalo is a no-code app builder for database-driven web apps and native iOS and Android apps—one version across all three platforms, published to the Apple App Store and Google Play. Organizations typically allocate significant modernization budget to user interface development - an area where Adalo delivers value through rapid app development.

The platform's responsive design capabilities ensure applications work across devices. The component system provides building blocks for interface requirements, from simple forms to complex visualizations explored in component marketplace guides.

Real-world modernization scenarios:

A regional bank modernizing its core banking system used traditional tools for backend transformation but chose Adalo for customer-facing mobile apps. Development time decreased from 6 months to 6 weeks. The native app publishing capabilities supported smooth app store submissions.

Manufacturing companies use Adalo to create inventory management interfaces connecting to modernized ERP systems. The visual development approach enables non-technical staff to maintain applications using Adalo's learning resources.

Integration strategies for mainframe modernization

Successful modernization requires sophisticated integration between legacy and modern systems. Adalo's External Collections (Professional plan and higher) connect to REST/JSON APIs only - no GraphQL or XML support - making it suitable for consuming modernized mainframe services through approaches detailed in API integration guides.

Key integration patterns:

• API Layer Pattern - Expose mainframe functions as REST APIs via z/OS Connect or similar
• Strangler Fig Approach - Gradually replace mainframe interfaces with Adalo apps
• Event-Driven Architecture - Use enterprise tools like IBM MQ, Apache Kafka, or CDC tools (Precisely, Qlik) for real-time data flows
• Near-real-time automation - Zapier integration for polling-based workflows

The Adalo API (Team & Business plans only) enables programmatic CRUD access to your app's data with a 5 requests/second rate limit. External Collections are also rate-limited. For high-throughput scenarios, consider Xano integration for scalable backend infrastructure.

Cost comparison across modernization platforms

Mainframe modernization costs vary based on approach and platform selection. Adalo's pricing offers predictable costs compared to usage-based enterprise platforms, as analyzed in cost comparison studies.

Platform cost analysis:

• Adalo - $45-250/month with specific app action and editor limits per plan
• AWS Mainframe Modernization - $0.103 per line of code plus runtime infrastructure costs
• IBM z/OS Connect - MSU-based pricing model
• OutSystems - Custom enterprise quotes required
• Traditional development - Often $100,000+ for simple applications

Organizations report 65% cost reduction using no-code platforms compared to traditional development. For frontend modernization, Adalo can deliver significant savings while accelerating development by 2x compared to traditional methods.

Forrester research demonstrates ROI ranging from 224% to 506% over three years for organizations adopting low-code platforms. The detailed pricing analysis shows how Adalo's model supports sustainable growth.

Modernization best practices for 2026

Successful mainframe modernization requires careful planning and phased execution. Organizations achieving the best outcomes follow proven patterns that minimize risk while maximizing value delivery, as outlined in app development best practices.

Recommended modernization approach:

1. Assessment Phase - Use AI-powered tools to analyze mainframe portfolio
2. API Enablement - Expose core mainframe services through REST APIs using z/OS Connect or similar
3. Frontend Modernization - Build modern interfaces with Adalo's no-code platform
4. Gradual Backend Migration - Transform backend services in phases
5. Complete Transformation - Achieve cloud-native architecture

The Adalo App Academy provides comprehensive training for modernization teams. With over 70 courses covering basics to advanced integrations, teams develop skills through structured learning paths.

Expert guidance accelerates modernization success. The Adalo Experts network provides specialized support for complex projects.

Success metrics and ROI

Organizations measure modernization success through multiple dimensions. According to Kyndryl's 2026 research, 96% of organizations plan to move workloads, with an average 36% to be migrated, while their 2026 survey shows approximately $25 million in average annual savings. Performance improvements often include faster development cycles and reduced deployment time.

Key performance indicators:

• Development velocity - Significant acceleration with low-code platforms
• Cost reduction - 30-80% savings reported versus traditional development
• Time to market - Weeks versus months for new applications
• User satisfaction - Improvements with modern interfaces
• Maintenance costs - Reduction in ongoing support

Adalo's showcase features success stories demonstrating ROI. Organizations typically recover modernization investments within 6-12 months through operational savings and improved customer experiences, as documented in case studies.

The 37 market growth statistics reveal accelerating adoption of no-code platforms. With 41% of businesses maintaining active citizen developer programs, modernization extends beyond IT departments.

Making the right modernization choice

Selecting ideal mainframe modernization tools depends on your organization's specific requirements, existing infrastructure, and transformation goals. For organizations prioritizing rapid user experience improvements, Adalo provides an effective starting point with its visual development platform and transparent pricing detailed in platform comparisons.

Begin your modernization journey by identifying customer-facing systems that would benefit from modern interfaces. Use Adalo's free plan to prototype solutions before committing to full development. Combine Adalo's frontend capabilities with backend modernization platforms for comprehensive transformation following proven strategies.

The future of enterprise computing lies in modern, cloud-native architectures. By choosing the right combination of tools, with Adalo enabling rapid frontend modernization, organizations can successfully transform legacy mainframes into competitive advantages. Start building your modernized applications today with Adalo's no-code platform and join thousands of organizations that have transformed their legacy systems through approaches detailed in our comprehensive guides.

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