Here are leading enterprise mobile solutions providers in Sri Lanka (strong in mobile app development, mobile middleware, enterprise-grade integrations and digital transformation). I’ve listed each with a short note and a source you can check.

• WSO2 — enterprise-grade API management, integration and identity platform with major engineering and operations in Colombo; widely used by banks and telcos. (en.wikipedia.org)
• hSenid Mobile Solutions — specialist in mobile/wireless middleware, telco and financial-services mobile platforms (SDP, messaging, enterprise mobile apps). (hsenidmobile.com)
• MillenniumIT ESP — enterprise systems integration, cloud, managed services and software engineering for banking, telco and large enterprises; offers platforms used by enterprise customers. (en.wikipedia.org)
• Virtusa (Sri Lanka delivery center) — large global digital engineering and IT services firm with deep mobile and digital-engagement capabilities and major delivery centers in Colombo. (Virtusa.com)
• Zone24x7 — Colombo-based engineering & R&D centre offering end-to-end enterprise software, embedded/IoT and mobile solutions for retail, telco and banking verticals. (zone24x7.com)
• Calcey — boutique product-engineering firm (Colombo) focused on enterprise mobile/web/cloud applications and long-term engineering engagements. (srilankabusiness.com)
• Fortude — enterprise digital solutions and consulting (ERP, cloud-native apps, app innovation) with a strong Sri Lanka presence and enterprise clients. (en.wikipedia.org)
• John Keells IT — part of John Keells Holdings; provides enterprise application development, integrations and mobile/industry-specific solutions. (en.wikipedia.org)

Quick tips to pick the right partner

• Match vertical experience (telco, banking, insurance, logistics) to your project.
• Check examples of enterprise deployments, scale (users/transactions), security/compliance and SLAs.
• Prefer providers with onshore delivery or a local Colombo delivery center if you need close collaboration.
• Ask for references, architecture diagrams, and a proof-of-concept timeline and cost estimate.

If you’d like, I can:

• Narrow this to the best 3 for a specific industry (banking, telecom, insurance, logistics), or
• Pull contact pages / recent case studies for any 3 providers you pick.