Best Cross-Platform App Development Companies in California

70 Companies - Rankings updated: September 04, 2026

Each agency listed on DesignRush is assessed for industry expertise and customer testimonials are evaluated in order to provide you with a vetted selection. Certain listings represent paid partnerships.

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United States × California × Cross-Platform Mobile App Development × AI × Clear Filters

  • ALFATEK

    High-Level Technology for Small and Large Business.

    ALFTEK offers full-service network infrastructure, system administration, network security, software development and other managed IT services. What's more, the company also integrates robust software solutions with cloud-based SaaS, PaaS and IaaS platforms for website and social & blog design...

    Top Services:

    • Software Development
    • Cybersecurity
    • IT Services
    • Managed Services
    • Web Design
    • Show more
    Location
    Concord, California
    Number of Employees
    Under 49
    Portfolios Count
    4 Projects Listed
    Visit Website View Profile

  • Utility

    Award-Winning Mobile Design & Development Agency with AI Expertise

    Utility is a premier digital product agency specializing in custom mobile apps, web platforms, and AI-powered solutions for forward-thinking startups and global brands including Airbnb, Coca-Cola, Samsung, the NBA, and Forbes...

    Top Services:

    • Mobile App Development
    • Software Development
    • AI Development
    • UI/UX Design
    • Digital Services
    • Show more
    Location
    Los Angeles, California
    Number of Employees
    100 - 249
    Average Hourly Rate
    $149/hr
    Minimal Budget
    $50,000 & Up
    Portfolios Count
    1 Project Listed
    Visit Website View Profile
    4.6 4.6 (10)

  • ACubetech Solutions Private Limited

    Take Charge Of Your Business Continuity

    ACUBE USAL LLC is a US registered custom Software development company delivering solutions in web, mobile & AI-driven solutions to companies across the US, Europe and Australia. We have proven experience in delivering solutions into education, healthcare, real-estate, E-commerce, logistics, food compliance...

    Top Services:

    • Mobile App Development
    Location
    Nevada City, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $20/hr
    Minimal Budget
    $1,000 - $10,000
    Portfolios Count
    1 Project Listed
    Visit Website View Profile

  • In Time Tec South Korea

    Best award-winning software development company in South Korea.

    Time Tec South Korea is a top-rated, multi-award-winning software development company providing a full suite of services and solutions like mobile application development, software development, Microsoft Dynamics 365 development, web development, ServiceNow consulting, and cybersecurity consulting to small...

    Top Services:

    • Software Development
    • Mobile App Development
    • Cybersecurity
    • AI Development
    • Show more
    Location
    Roseville, California
    Number of Employees
    1000 & Up
    Average Hourly Rate
    $25/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile

  • Rocket Systems

    Rocket your business forward with our expertise.

    Rocket Systems is focused on producing high-quality code, we take extra precautions to ensure that our technological approach is congruent with the ambitions of our customers. Additionally, we strive to create code bases that are both scalable and easily maintained. In order to construct a digital product...

    Top Services:

    • Web Development
    • Web Design
    • IoT
    • AI Development
    • Mobile App Development
    • Show more
    Location
    Sacramento, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $25/hr
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile

  • Web Design Mechanic

    A Leading Web Design & Development Agency

    Web Design Mechanic creates clean, custom websites and digital experiences build to match your business goals. "No templates", just thoughtful design and smart development. We also offer digital marketing services like, Search Engine Optimization, Social Media Marketing, Online Reputation Management, and...

    Top Services:

    • Web Design
    • Web Development
    • Branding
    • eCommerce Development
    • Video Production
    • Show more
    Location
    Fremont, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $25/hr
    Minimal Budget
    $1,000 - $10,000
    Portfolios Count
    1 Project Listed
    Visit Website View Profile

  • Royce Web Solutions

    Affordable & Premium Web Development Company

    Royce Web Solutions is a full service digital agency specializing in custom websites, e-commerce stores, SaaS platforms, and AI-Powered web and mobile apps. We help startups and businesses turn ideas into fast, scalable and user-friendly digital products...

    Top Services:

    • Web Design
    • eCommerce Development
    • Mobile App Development
    • Web Development
    • Show more
    Location
    Mountain View, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $35/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile

  • Kingdom Vision

    We Build Cool Stuff With Cool People...

    Kingdom Vision is a digital agency specializing in web design, web development, and custom software solutions for businesses and startups. The company offers a range of services including mobile app development, CMS development, branding, and digital marketing to help clients build and grow their online...

    Top Services:

    • Web Design
    • Branding
    • Web Development
    • Mobile App Development
    • Digital Marketing
    • Show more
    Location
    San Jose, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $25/hr
    Minimal Budget
    Under $1,000
    Visit Website View Profile

  • Top Remotely

    Top 1% Tech Talent with 1500+ In-house Developers

    We don't just build software at Top Remotely we create solutions that work, scale, and impress. With a powerhouse team of 150+ in-house developers, we turn complex challenges into seamless digital experiences. Whether you need custom software, enterprise platforms, or next-gen IT solutions, we bring the Top...

    Top Services:

    • Mobile App Development
    • Software Development
    • DevOps Consulting
    • IT Services
    • Web Development
    • Show more
    Location
    Los Angeles, California
    Number of Employees
    500 - 999
    Average Hourly Rate
    $20/hr
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile

  • Allusive Digital

    Proven Excellence Through Custom Web Design and Development Services.

    Allusive Digital is a creative and marketing agency that helps businesses grow through branding, web design, content development, and digital marketing. The agency blends thoughtful strategy with polished creative execution to help clients increase visibility, strengthen their identity, and connect with their...

    Top Services:

    • Web Development
    • eCommerce Development
    • Web Design
    • WordPress Website Design
    • AI Development
    • Show more
    Location
    Los Angeles, California
    Number of Employees
    Under 49
    Visit Website View Profile
    5.0 5.0 (5)

  • Teamvoy

    We Bring The Tech. You Get The Wins.

    Teamvoy is an AI engineering and transformation partner. We help companies make smarter technology decisions and turn them into production-ready software...

    Top Services:

    • Software Development
    • AI Development
    • Design Services
    • Web Design
    • UI/UX Design
    • Show more
    Location
    Covina, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $50/hr
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile
    4.7 4.7 (29)

  • Bay Area Coders

    Strategy, design, engineering, and AI

    Bay Area Coders is a San Francisco-based product and engineering studio working with venture-backed startups and growth-stage companies since 2016. We combine strategy, design, engineering, and AI to help teams ship real products and modernize existing ones...

    Top Services:

    • Software Development
    • Web Development
    • Mobile App Development
    • AI Development
    • Design Services
    • Show more
    Location
    Roseville, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $100/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile

  • FACTn Software

    Empowering Innovation, Connecting Excellence

    FACTn Software, your trusted partner in software engineering outsourcing solutions. Founded with a passion for technological innovation and a commitment to excellence, FACTn Software is dedicated to providing top-tier software engineering talent to companies in the Scandinavian region and beyond...

    Top Services:

    • Software Development
    • Mobile App Development
    • AI Development
    • Cloud Consulting
    • Managed Services
    • Show more
    Location
    Los Angeles, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $45/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile
    5.0 5.0 (10)

  • Born West Inc.

    We Build Digital Products, Experiences, And Systems ‍that Matter.

    Born West is a creative tech agency. We turn ambitious ideas into working software from inception to launch. Our senior strategists, designers, and engineers work as one team to shape digital products, AI-powered tools, platforms, and experiences that are thoughtful, scalable, and built to ship...

    Top Services:

    • Product Design
    • Web Design
    • eCommerce Development
    • Web Development
    • WordPress Website Design
    • Show more
    Location
    Concord, California
    Number of Employees
    Under 49
    Average Hourly Rate
    $200/hr
    Visit Website View Profile

  • CloneAppz

    Verified Verified by the DesignRush team for authenticity and credibility.

    White label & clone app development company

    CloneAppz delivers white label and clone app solutions that help businesses go live faster. We combine proven technology with smart customization to give you a platform that genuinely represents your brand and supports real growth...

    Top Services:

    • Mobile App Development
    Location
    San Francisco, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $20/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile

  • TechMave Software

    You Think We Will Deliver

    TechMave Software LLP delivers innovative web, mobile, and AI solutions tailored to business needs. Our team combines creativity, technology, and strategy to build impactful digital products that empower brands globally...

    Top Services:

    • Design Services
    • eCommerce Development
    • Web Development
    • AI Development
    • Mobile App Development
    • Show more
    Location
    Mountain View, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $11/hr
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile
    5.0 5.0 (30)

  • Rytsense Technologies

    Leading Global Digital Transformation

    Rytsense Technologies is an AI-driven technology company specializing in AI development services, machine learning solutions, and intelligent automation. We help businesses build advanced AI applications, integrate AI models into existing systems, and transform data into actionable insights...

    Top Services:

    • AI Development
    • Mobile App Development
    • Software Development
    • Business Consulting
    • Show more
    Location
    Mountain View, California
    Number of Employees
    100 - 249
    Average Hourly Rate
    $25/hr
    Minimal Budget
    Under $1,000
    Visit Website View Profile
    5.0 5.0 (67)

  • TechnoBrains Business Solutions

    Empowering Businesses Through Innovative Software Development

    TechnoBrains Business Solutions is a global software development and AI solutions company founded in 2009, delivering custom web, mobile, AI, and enterprise software solutions for startups, SMEs, and established enterprises worldwide. Headquartered in Ahmedabad, India, with a presence in the United States...

    Top Services:

    • AI Development
    • Mobile App Development
    • Software Development
    • eCommerce Development
    • Web Development
    • Show more
    Location
    San Francisco, California
    Number of Employees
    50 - 99
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile
    4.8 4.8 (26)

  • NextOlive

    Grow with Technology.

    We have a Team of 100+ Skilled App Developers who thrive on rolling up their sleeves and solving your IT problems and meeting your business needs like APP Development, Software Development, Cloud Consulting, Generative AI Development, Cyber Security Services, Custom ERP Software Development, and Web...

    Top Services:

    • AI Development
    • Mobile App Development
    • Software Development
    • Blockchain
    • Software Testing
    • Show more
    Location
    Irvine, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $25/hr
    Minimal Budget
    $10,000 - $25,000
    Visit Website View Profile

  • TST Technology

    Your Trusted IT Consulting Company for Business Success.

    TST Technology is an IT consulting company that offers services such as UI/UX design, web and mobile app development, software development, and SaaS product development. They have completed over 40 projects across 15+ industries...

    Top Services:

    • IT Services
    • UI/UX Design
    • Mobile App Development
    • Software Development
    • Web Development
    • Show more
    Location
    Los Angeles, California
    Number of Employees
    50 - 99
    Average Hourly Rate
    $50/hr
    Minimal Budget
    $1,000 - $10,000
    Visit Website View Profile
    5.0 5.0 (22)

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