Our analysts identified the top outsourcing software development companies in California providing cutting-edge services that answer key business problems, from building technical software, designing websites or mobile apps to integrating operating systems and more. Narrow down your search by team size, budget, reviews and more to select the best developer for your company’s needs.
Organic rankings are determined by five factors: top services, reviews, portfolio, awards/press, and team expertise. Sponsored listings pay for a placement that appears above organic positions. Sponsorship does not affect star ratings or review content - read more on our methodology page.
Your trusted AI software development partner
When startups and enterprise clients need AI-driven software or staffing, Diffco delivers custom mobile, web, and IoT applications backed by 17 years of delivery experience. San Jose-headquartered, the team has built solutions for American Express, Starbucks, Whole Foods, and Mars, using React, Node.js...
Top Services:
- AI Development
- Software Development
- Staff Augmentation
- Mobile App Development
- Web Development
- Show more
- Location
- San Jose, California
- Number of Employees
- 50 - 99
- Average Hourly Rate
- $110/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 31 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsDiffco Services
Data sourced from the agency's DesignRush profileMars Food Rocket FlashGrid Nokia Instreamatic Quire Legionfarm Latoken Genius One Shift
Diffco Reviews & Testimonials

Mobile App Development Review from Elvera Kaparchuk
SaveIT is receipt management on autopilot. You connect your email once, and we import your receipts, extract every line item with AI, categorize it, and sync it with QuickBooks. The AI isn't a feature of the product, it is the product. If it reads a receipt wrong, everything downstream is wrong. We brought Diffco in to work on that core. Since April they've worked on our AI models, fixed security problems in the platform, and helped us build a real strategy around where AI belongs and where a conventional solution is the better call. The most important change was measurement: extraction accuracy is now a number we evaluate every change against, instead of something we judge by trying a handful of receipts. They were also honest in a way I didn't expect from an AI firm. When we assumed a problem needed a stronger model, they showed us it was in our data. That saved us time and money. They continue to support the AI side of the product, and they're easy to work with; direct, technically deep, and clear about trade-offs.

AI Development Review from Ivan Pasichnyk
We brought Diffco in to deliver the AI and computer vision components for one of our clients, an image generation startup. Because the work sat inside our own client relationship, we needed a partner we could trust to operate at our standard without us managing them day to day - and that is exactly what we got. Diffco owned the technical approach, built the computer vision and AI layer, and delivered the full scope in three months, on schedule. The engineering quality was high, they raised the right questions early instead of late, and they handled the confidentiality the project required without us having to chase it. After delivery they stayed on to support the system, which mattered to us as much as the build itself. When you subcontract a technical project inside your own client relationship, the risk is that the partner makes you look bad. Diffco did the opposite. They've earned our trust and we'd work with them again.

AI Development Review from Oleg Sotnikov
Diffco built a complex, production-grade AI agentic system and backend for our client's fintech platform owning architecture, AI/ML components, and AI agents in a security- and compliance-sensitive environment. They delivered on time and within budget, communicated proactively, and operated like part of our own team, taking ownership and suggesting better solutions throughout. Deep AI/ML and senior backend expertise. We'd happily work with them again.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsWhere Exceptional Apps Are Just The Beginning
When enterprises need custom apps across healthcare, fintech, and ecommerce, BitsWits delivers mobile and web platforms using React Native, Flutter, Swift, and blockchain stacks. The Houston-based studio handles iOS, Android, and cross-platform builds with in-house AI, IoT, and AR/VR capabilities. Clients...
Top Services:
- Mobile App Development
- Software Development
- VR/AR
- Blockchain
- AI Development
- Show more
- Location
- Los Angeles, California
- Number of Employees
- 100 - 249
- Average Hourly Rate
- $25/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 12 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsBitsWits Services
Data sourced from the agency's DesignRush profileFitNow Wisu Soul Scribe Grease Monkey Beats
BitsWits Reviews & Testimonials

Mobile App Development Review from Sydney Malone
With the development of our Mobile App, BitsWits performed a fantastic job. Their team was quick to respond and produced a great application that runs smoothly on all platforms. We are quite happy with the result.

Mobile App Development Review from Benson Sung
They created a Mobile app for Medical services, and patient management has changed greatly as a result. The app works well with our current systems, is safe, and is simple to use. Their team produced a top-notch product on schedule while paying close attention to our unique requirements. We are really pleased with their work and heartily recommend BitsWits to anyone in need of app development services.

Mobile App Development Review from Steve Garry
The outcomes of our collaboration with BitsWits to develop an Online Food delivery app were outstanding. Real-time tracking is integrated into the app, which makes it easy to use and has significantly enhanced our customer support. Their development staff was quick to respond and took care of all of our requests. We couldn't be more pleased with the result!
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsEmpower Your Business With Future Ready IT Solutions
For offshore and onshore software builds, A3Logics delivers custom development, mobile applications, and cloud modernization across enterprise and startup clients. The Carlsbad-based team maintains development centers in India and Singapore, supporting Fortune 500 companies and ISVs with agile engineering...
Top Services:
- Mobile App Development
- Software Development
- Big Data Analytics
- Blockchain
- AI Development
- Show more
- Location
- Carlsbad, California
- Number of Employees
- 250 - 499
- Average Hourly Rate
- $35/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 13 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsA3Logics Services
Data sourced from the agency's DesignRush profilemyEnPro Will2click CareGiver Future Institute Tabbi Daylight Corp My Finny Playmaker Ghost Kitchen Hastens
A3Logics Reviews & Testimonials

Software Development Review from Elizabeth Sheehan
Our main goal was to update our web presence to more accurately represent our proficiency in IT consulting and services. Our prior website was disorganized, had poor performance, and failed to adequately convey our expertise in customer relationship management (CRM), customer communications management (CCM), and content management systems (CMS). We required a highly functional, aesthetically pleasing, and scalable website that could captivate users, offer smooth navigation, and blend in seamlessly with our current technology stack.They have perfect attention to detail. They took care of everything, from making sure the font and color scheme matched our corporate identity to making every user interaction as efficient as possible. The outcome was a website that serves as a potent instrument for business expansion in addition to being aesthetically pleasing. They were always helpful and quick to respond when we had questions after the launch.

Big Data Analytics Review from Adam Leeman
A3logics main strength was their intuitive understanding of what I was looking for. They were highly communicative regarding updates and required almost no guidance or oversight. Moreover, they were extremely creative in areas I hadn't even considered, coming up with impressive solutions.

Software Development Review from Mubarak Muaz
A3logic provided software development based on the detailed briefing that we gave them, ensuring that every aspect aligned with our brand identity and user needs. They carefully analyzed our requirements, conducted research, and proposed design solutions that enhanced usability and engagement. A3logic was a very professional company. They managed the project well and delivered on time and within budget. They were very responsive and timely in their communication. I was impressed with how enthusiastic the A3logic team was about their work. They cared about my project and treated it as their own. They were a great team.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsFUELING DISRUPTION
EffectiveSoft is an AI-enabled product engineering company focused on digital products and enterprise systems. We combine software engineering, UX expertise, and AI capabilities to help companies build products that can adapt to changing requirements, integrations, and growth...
Top Services:
- Software Development
- Mobile App Development
- Big Data Analytics
- AI Development
- ERP Consulting
- Show more
- Location
- San Diego, California
- Number of Employees
- 250 - 499
- Average Hourly Rate
- $50/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 29 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsEffectiveSoft Services
Data sourced from the agency's DesignRush profileCITY INDEX TruBridge CNote Plato Intelon Optics InCheq Nissin Foods Soutron Ltd. BullionRock InContinuum
EffectiveSoft Reviews & Testimonials

Software Development Review from Alex Silverstein
Over the past 13 years, I’ve valued the opportunity to work alongside this team. Their expertise played a central role in my company’s success, and I’ve come to rely on them for their consistency, attention to detail, and thoughtful approach.

Software Development Review from Philipe Araujo
We have had a highly positive experience utilizing EffectiveSoft's staff augmentation services for our Business Analyst and Quality Engineer needs. The professionals provided were not only highly skilled and knowledgeable but also integrated seamlessly with our existing team, requiring minimal ramp-up time. Their expertise in their respective fields significantly enhanced our project's efficiency and overall quality. We confidently recommend EffectiveSoft for any organization seeking top-tier talent to augment their teams and drive successful project outcomes.
Software Development Review from Sasja Ihn Christensen
Maersk Broker is pleased to provide this reference letter for EffectiveSoft, our trusted collaborator for complex web projects. From the initial stages of our projects, the team at EffectiveSoft demonstrated a deep understanding of our requirements and have been apro-active part of any problem-solving process. The team of offshore developers has been well-run through their lead developer, and we have only experienced a professional approach to our projects, as well as a pleasant and trust-based collaboration = between all members in the EffectiveSoft team and our own team. EffectiveSoft has furthermore proved to be highly flexible, adapting to our evolving needs and delivering reliable results under shifting circumstances and shifting priorities. They have furthermore been very quick to find and add the necessary resources to the team when needed, and we have only experienced professional and highly skilled consultants. This has also made on-boarding into projects faster and more efficient.In conclusion, it has been a pleasure working with EffectiveSoft, and I have no doubt that they will continue to be an asset to any collaborators in the future, adding value through their professionalism, dedication and understanding of business needs.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsYou Think It, We'll Build It.
Idea Maker is a U.S.-based software development agency helping businesses transform ideas into scalable digital products. Our expert team specializes equally in mobile apps, custom software, AI-powered solutions, and modern web platforms...
Top Services:
- Mobile App Development
- Software Development
- Web Development
- AI Development
- Web Design
- Show more
- Location
- Irvine, California
- Number of Employees
- Under 49
- Average Hourly Rate
- $125/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 10 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsIdea Maker Services
Data sourced from the agency's DesignRush profilePlane Fax Generac Politifact Outschool Advance CPE AES Blodgic Fujikikai Yellowbook CPE
Idea Maker Reviews & Testimonials

Software Development Review from Jessi Navarro
IdeaMaker supported Poynter's Digital Experience work and our PolitiFact site migration to Wordpress. The migration launched successfully, moving our infrastructure forward significantly at a pivotal time and we appreciated their help getting us onto the new system.

Web Development Review from Meghan Wallace
When you're launching a nonprofit from scratch, every resource matters and Tom stepped in with extraordinary generosity. He brought his team in to help build the Survive Out Loud website, and the result is something were genuinely proud of.Tom and his team didn't just build a site. They listened carefully, asked thoughtful questions, and translated our vision into something clean, professional, and aligned with our mission. They were patient, collaborative, and incredibly responsive throughout the entire process.For a small organization trying to get off the ground, this kind of support is transformational. We are deeply grateful for Tom and his team and would recommend them without hesitation

Software Development Review from Kevin Nagel, MBA
IdeaMaker did an amazing job developing our cutting-edge software. They took our concept and turned it into a fully functional, scalable software platform that truly brought our vision to life. Their technical expertise, clear communication, and problem-solving mindset made the entire process seamless. IdeaMaker consistently delivered high-quality work on time and with care. We couldn't have asked for a better development partner!
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsNearshore Software Development Services
Clear your backlog and ship products you're proud of faster with our nearshore software development resources. We provides highly skilled, team-based resources to companies that need tech talent fast...
Top Services:
- Mobile App Development
- Software Development
- Staff Augmentation
- Web Development
- eCommerce Development
- Show more
- Location
- San Francisco, California
- Number of Employees
- Under 49
- Average Hourly Rate
- $70/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 8 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsAdmios Services
Data sourced from the agency's DesignRush profileConverse Anaplan Zignal Labs Contract Pod AI Collective Health Terraformation Conductor Shop Ware Symphony Off the Grid
Admios Reviews & Testimonials

Web Development Review from Will McDonald
I was able to dictate requirements at a high level without having to deal with the details. The Admios team was able to make technical level decisions on their own. They were a first class partner of the team.

Software Development Review from Mark Griffin
Due to past experiences, Latent AI is always cautious when hiring external engineering resources for a project. But collaborating with Admios is a breath of fresh air. The agencys account manager is nothing short of professional, attentive, and understanding of client needs. Furthermore, Admios seasoned and self-sufficient engineers fit seamlessly into the Latent AI culture. The team treats and trusts them as one of their own. (Verified via email)

Mobile App Development Review from Matt Attaway
Off the Grid has had a longstanding developer partnership with Admios. Recently, the client trusted Admios with building a complex React Native POS system and a guest order-ahead app. Given the complexities of the project, Off the Grid wouldn't have chosen any other agency to work with. The Admios' developers did an excellent job, the management was proactive, and the software quality is exceptional. Admios is highly recommended. (Verified via email)
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsCertified E-Commerce Development Company
Certified E-Commerce Development Company...
Top Services:
- eCommerce Development
- Web Development
- IT Services
- Web Design
- Mobile App Development
- Show more
- Location
- San Francisco, California
- Number of Employees
- 50 - 99
- Average Hourly Rate
- $40/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 16 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsDinarys Services
Data sourced from the agency's DesignRush profileAroma Kava LastBid Budu Sushi Magento 2 Migration Rite Space Bookbreakrs Can Vivat Udifo ServisBook
Dinarys Reviews & Testimonials

eCommerce Development Review from André Schörnig
We have been working with Dinarys on our Shopify store for quite some time, and the experience has been great. From the very beginning, communication was clear, efficient, and reliable. The Dinarys team consistently delivered detailed proposals, stuck to agreed timelines, and offered well-structured solutions tailored to our needs. Their technical expertise is impressive, but what really sets them apart is their proactive attitude and genuine commitment to our project. Whenever we had questions or changes, they responded quickly and constructively. Its a true pleasure to work with a partner who feels like an extension of our own team. Highly recommended!

Web Development Review from Nissrine Kohen
Weve been working with Dinarys for quite some time now, mainly collaborating on Magento and Shopware development projects. Their developers consistently show solid technical expertise and a good understanding of our expectations and workflow.Communication is generally smooth, and response times are quick. Whenever issues arise, the team is open to feedback and acts quickly to improve. Over time, weve seen a positive evolution in their proactiveness and alignment with our teams way of working.They are flexible and collaborative, and its clear that they genuinely aim to build long-term partnerships. For the quality delivered, we feel the pricing is fair and transparent.All in all, weve been satisfied with our cooperation and would recommend Dinarys as a development partner, especially for companies looking for experienced backend developers in Magento and Shopware.
Nina Liashuk's Review Sourced from Google
Smooth, reliable cooperation every step of the way. They're quick to respond, easy to work with, and consistently deliver strong results. Their reliability and the quality of support have stood out the most. A team we would recommend without hesitation.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsDigital products. Done beautifully.
Wve Labs is a digital product company bringing strategy, design, and engineering together to create mobile apps, web platforms, and custom software. Since 2015, we have partnered with startups, growth companies, and global organizations to design, build, and scale digital products...
Top Services:
- Mobile App Development
- Software Development
- UI/UX Design
- Product Design
- Web Development
- Show more
- Location
- Costa Mesa, California
- Number of Employees
- Under 49
- Average Hourly Rate
- $50/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 5 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsWVE Media Services
Data sourced from the agency's DesignRush profileSony Honda Guardian Maui Jim Com-Power VIZI Super Gems Jewelry The Now Bonfire Crave on Campus
WVE Media Reviews & Testimonials
Brayden Yarbrough's Review Sourced from Google
Working with Wve Labs has been an outstanding experience. Their communication is exceptional—they keep me informed throughout every stage of the process and are always quick to answer questions and provide thoughtful feedback.The app design has exceeded my expectations, and they consistently stay on track with the timelines they set. What really sets Wve Labs apart is their ability to brainstorm and collaborate. They don't just build my app—they help refine my ideas, offer creative solutions, and provide valuable insights that continue to make the final product even better.It's clear that their team consists of true experts in digital product development. Whether it's strategy, design, or technical execution, they bring a level of professionalism, creativity, and expertise that's hard to find. I'm excited to continue working with them and highly recommend Wve Labs to anyone looking for a development partner that genuinely cares about the success of their project.Founder, GameDay Bites
delaney day's Review Sourced from Google
I have had the pleasure of working at Wve Labs for over a year now, and it has been an absolutely amazing experience. The leadership is dedicated to ensuring each employee’s success and is highly focused on the company’s growth. Being part of such a dynamic and diverse team with a fantastic client base makes me proud.The company offers numerous opportunities for professional development, and the collaborative atmosphere encourages innovation and creativity. Every day presents new challenges and learning opportunities, making the work both engaging and fulfilling.Additionally, Wve Labs prioritizes community involvement and social responsibility, frequently organizing events and initiatives that give back to society. This comprehensive approach not only enriches our corporate culture but also instills a sense of contributing to a larger cause.In conclusion, my time at Wve Labs has been extremely fulfilling, and I look forward to the future as we continue to grow and innovate together.
Jack Joyce's Review Sourced from Google
Working at Wve Labs has been an incredible experience, and I can't speak highly enough about the company's atmosphere and culture. From the moment I joined, I was welcomed into a collaborative and supportive environment where creativity and innovation are not just encouraged but celebrated.The culture at Wve Labs is one of inclusivity and respect. Every team member's ideas are valued, and there's a strong sense of camaraderie that makes coming to work each day a pleasure. The leadership team is approachable and genuinely cares about the growth and well-being of every employee, fostering a workplace where people feel motivated to do their best.Wve Labs truly excels in creating a positive and dynamic work environment. The office is buzzing with energy, driven by passionate individuals who are dedicated to delivering top-notch results. The company also offers numerous opportunities for professional development, which has allowed me to expand my skill set and grow in my career.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsYour AI-Driven Software Development Partner
Savvycom is an AI-driven software development and IT consulting company founded in 2009, helping enterprises design, build, and modernize digital systems that deliver measurable business outcomes. Recognized as one of Vietnams Top 10 Digital Technology Companies, Savvycom partners with organizations...
Top Services:
- Mobile App Development
- Software Development
- Web Development
- IT Services
- AI Development
- Show more
- Location
- Laguna Beach, California
- Number of Employees
- 500 - 999
- Average Hourly Rate
- $40/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 9 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsSavvycom Services
Data sourced from the agency's DesignRush profileKB Bank Citeco. Capsikin Path. North America & Europe: TaylorMade
Savvycom Reviews & Testimonials
Amelia's Review Sourced from Google
Working with Savvycom was a positive experience. The team was professional, responsive, and delivered quality work on time. Communication was smooth, and they were always willing to help when needed. Highly satisfied with the collaboration.
Nguyên Ngọc's Review Sourced from Google
From my perspective as a former employee: I worked here for almost a year. Colleagues and staffs here are pretty open-minded but employees are highly underpaid. Also in order to get a job here you must have decent technical skills and English language ability.Pros: nice office, friendly staffs that really take care of employeesCons: underpaid salary
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsTranslating Ideas & Research to Market
KritiKal Solutions is a technology design house and holds 22+ years of experience in AI, Computer Vision, Software Applications, Cloud and Mobile-based Solutions, Embedded Systems, Generative AI and Large Language Models. We specialize in R&D, product engineering, and innovation services...
Top Services:
- AI Development
- IoT
- Mobile App Development
- Software Development
- Wearables
- Show more
- Location
- Los Angeles, California
- Number of Employees
- 100 - 249
- Average Hourly Rate
- $25/hr
- Minimal Budget
- $25,000 - $50,000
- Portfolios Count
- 4 Projects Listed
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsKritikal Solution Services
Data sourced from the agency's DesignRush profileVector USA BYJU'S P&G Columbus Continental Honeywell ITC Stryker G&D University of Berkeley
Kritikal Solution Reviews & Testimonials
Aakriti Bhatnagar's Review Sourced from Google
Great place to work.Very good learning opportunity.Best place for freshers to learn and gain knowledge.Supportive and understanding colleagues.
Jobin John's Review Sourced from Google
One of the best aspects of working at KritiKal Solutions is the opportunity to collaborate with talented professionals across multiple domains. The company promotes a culture of innovation, knowledge sharing, and continuous improvement.
twinkle kumari's Review Sourced from Google
A great workplace that encourages continuous learning, teamwork, and professional growth. The management maintains an open-door policy, making it easy to share ideas and collaborate across all levels of the organization.
Reviews verified by DesignRush and sourced from the agency's profile View All ReviewsSoftware Dev & Staffing Company
We were established in 2003 as a software development (web/mobile) and staffing company, and have extensive experience in all phases of the development lifecycle, from design to development, software QA, and UI/UX...
Top Services:
- Software Development
- UI/UX Design
- Location
- San Francisco, California
- Number of Employees
- 100 - 249
- Average Hourly Rate
- $49/hr
- Minimal Budget
- $25,000 - $50,000
Data sourced from the agency's DesignRush profile, its website, and other relevant accountsCreativa Studios Services
Data sourced from the agency's DesignRush profileKMStandards Banco Davivienda Rathe Pollo Campero Cuestamoras.
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