Best US Cross-Platform App Development Companies

3 Companies - Rankings updated: September 03, 2026

All agencies are evaluated on DesignRush for demonstrated expertise and authentic client reviews to support your decision. Certain placements are paid.

United States × Cross-Platform Mobile App Development × Design × $50,000 & Up × Clear Filters
  • Award Winning Custom Development Experts | ERP Integration | Shopify/BigCommerce

    QOLOS (pronounced "koh-lohs") is a U.S.-based software development company, specializing in building custom, high-performance digital solutions for brands that demand innovation. From complex ERP integrations to e-commerce solutions - you are in good hands with QOLOS...

    Top Services:

    • Web Development
    • eCommerce Development
    • WordPress Website Design
    • Software Development
    • UI/UX Design
    • Show more
    Location
    Green Bay, Wisconsin
    Number of Employees
    50 - 99
    Average Hourly Rate
    $150/hr
    Minimal Budget
    $50,000 & Up

    QOLOS Services

    • Web Development
    • eCommerce Development
    • WordPress Website Design
    • Software Development
    • UI/UX Design
    • SEO
    • Software Testing
    • Mobile App Development
    • ERP Consulting
    • DevOps Consulting
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Thermos
    • Certco
    • Stryker
    • Louisville Vegan Jerky
    • Dallas Morning News
    • Dallas Police Department
    • Bancroft and Sons
    • Schneider National
    • Cocktail Courier
    • Restaurant Warehouse
    Data sourced from the agency's DesignRush profile

    QOLOS Reviews & Testimonials

    • Amanda Viviano
      Amanda Viviano Vice President at Bartz Viviano
      5.0

      WooCommerce Review from Amanda Viviano

      We hired Qolos to build our local florist shop's website on WordPress and WooCommerce, and we couldn't be happier with the results. From the start, they took the time to understand our business and created a site that's not only beautiful but easy for our customers to browse and shop. The WooCommerce setup was seamless, our online ordering works exactly the way we needed it to. But what really sets Qolos apart is their ongoing monthly maintenance. We never have to worry about updates, security, or technical issues because they stay on top of everything. Any time we've had a question or a small change request, they've been responsive and professional. As a small local business, it means a lot to work with a team that genuinely cares about keeping our site running smoothly. Qolos has been a true partner, not just a vendor. Highly recommend them to any local business looking for reliable web design and maintenance!

    • Sanjay Singh
      Sanjay Singh Manager at JCB India Ltd.
      5.0

      Web Development Review from Sanjay Singh

      I kept getting negative reviews about my app for technical glitches, heating issues, functionality, loading time, crashing, and more bugs. So, I reached out to QOLOS after going through 2-3 renowned review platforms. I explained my app issue to the team, and they did tremendous work with their mobile testing solutions. Also, I wanted to build a website for my app. They created a feature-rich and seamless website.

    • Sarah Nesheim
      Sarah Nesheim Co-Founder at Crafted
      5.0

      Shopify Review from Sarah Nesheim

      Working with QOLOS was the best decision I have made in regards to scaling my business. They are professional, so creative, they communicate every step of the way and their pricing is fair for the highest quality work. The designer of our logo and website did it well and I am so impressed and proud of the final product! the designer listened and knew exactly what I wanted which made the process so simple. Seriously could not recommend QOLOS more!

    Reviews verified by DesignRush and sourced from the agency's profile View All Reviews
  • We Build Innovative Technology.

    Applications and platforms proudly built here in the USA. We have assisted some of the most prominent global brands operating in complex and heavily regulated sectors in successfully launching software solutions that underpin their go-to-market strategy, ensuring a world-class customer experience...

    Top Services:

    • Software Development
    • Mobile App Development
    • UI/UX Design
    • Product Design
    • Creative Services
    • Show more
    Location
    Irvine, California
    Number of Employees
    Under 49
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    14 Projects Listed

    Kingsmen Digital Ventures Services

    • Software Development
    • Mobile App Development
    • UI/UX Design
    • Product Design
    • Creative Services
    • Web Development
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • Evolus
    • Revance
    • Merz Aesthetics
    • PTC
    • Kareo
    • Microsoft
    • Quiksilver
    • Casamigos Tequila
    • VantagePoint
    Data sourced from the agency's DesignRush profile
  • The App Development partner for leading companies

    ThinkUp is a quality-obsessed digital product development company specializing in mobile apps and unique user experiences. We create world-class digital products and exceptional mobile experiences for startups, unicorns, and organizations such as dLocal, AstroPay, Itau Bank, OCA, and Bodhi...

    Top Services:

    • Mobile App Development
    • UI/UX Design
    Location
    Minneapolis, Minnesota
    Number of Employees
    50 - 99
    Average Hourly Rate
    $50/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    9 Projects Listed

    ThinkUp Services

    • Mobile App Development
    • UI/UX Design
    Data sourced from the agency's DesignRush profile, its website, and other relevant accounts
    • dLocal
    • AstroPay
    • Itaú Bank
    • Bodhi
    • Bonoxs
    • Club Atlético Peñarol
    Data sourced from the agency's DesignRush profile

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