Voice agent client
An iOS and Android app for an AI startup whose product is a voice agent, with streaming audio, interruptions, transcripts and a fallback when the network drops. The model and prompts stay on your servers.
Mobile App Development · San Francisco, CA
Mobile App Development in San Francisco
Mobile app development in San Francisco often means adding mobile capacity to a team that already has engineers. We work remotely with SaaS companies and AI startups in the Bay Area, build the iOS and Android app against your API, and leave code your own team can own.
- Mobile clients for LLM and voice products
- Built against your API and design system
- Code in your repos from the first commit
- 01 Discovery call
- 02 Scope and estimate
- 03 Design and prototype
- 04 Build and test
- 05 Store release
When the Bay Area team is busy with the platform
San Francisco companies seldom need generalist engineers from outside. What they lack is mobile. The web product is growing, enterprise customers ask about an app on every renewal call, and the people who know the platform best are booked for the next two quarters. Hiring a mobile team in the Bay Area is slow and expensive, and moving platform engineers onto the app stalls the roadmap they were hired for.
We act as that missing mobile team. Before writing code we read your API docs, design system and auth setup, and agree on how pull requests get reviewed. For AI products the model stays your backend’s job, and we focus on what the phone does well: streaming responses, audio, the camera and offline drafts. Every screen goes through your reviewers, so handing the app to a future in-house hire is a matter of onboarding.
Typical mobile app development projects in San Francisco
SaaS field companion
The few actions customers of a B2B platform need away from a laptop, like approvals, alerts and photo uploads, built in React Native against the existing API and design tokens.
Camera-first AI MVP
A consumer app that turns a photo of a receipt, a label or a document into something useful, built to measure retention with beta users before a seed round.
Budgeting an app for a Bay Area startup
Each package below is fixed-price, so the plan carries one known number instead of an open-ended hiring budget. Engineers added to your team on an ongoing basis run at $25–50 per hour.
| Package | Proof of concept | MVP | Market ready | Enterprise |
|---|---|---|---|---|
| Price | From $2,400 | From $9,600 | From $24,000 | From $48,000 |
| Typical timeline | 2–4 weeks | 2–4 months | 4–7 months | 7+ months |
| Usual SF scope | Prototype of the AI or mobile flow to test with design partners | Companion or AI app on your API with auth, core actions and push | Offline support, analytics, in-app purchases and release automation in your CI | Multi-tenant app with SSO, admin roles, audit logs and an enterprise security review |
Technologies
- Swift, SwiftUI
- Kotlin, Jetpack Compose
- Flutter
- React Native
- Node.js, Laravel, Python
- Firebase, AWS, Google Cloud
- Stripe, Apple Pay, Google Pay
- OpenAI and other LLM APIs
Collaboration
Working with San Francisco teams
We join your Slack, GitHub and sprint rituals and keep U.S. business hours, so a question in a code review gets an answer while your team is still at work. Pull requests follow your conventions and go through your reviewers, which keeps the app readable to the people who will maintain it.
Our U.S. operations are facilitated through Orcatec LLC, our trusted American business partner, enabling seamless collaboration with clients across the United States.
Related work
Automotive · Marketplace
Currux
From a simple request website to an app that rents a car in minutes.
Minutes to rent a car from the mobile app
Read the case study →
Fitness · Mobile product
Spinning
Studio classes, delivered on demand to subscribers on iOS and Android.
2 mobile platforms: iOS and Android
Read the case study →Frequently asked questions
Can you build the mobile client for our LLM or voice agent product?
Yes. Your backend keeps the model, prompts and keys, and the app handles streaming text or audio, interruptions, retries and caching. For small tasks like transcription we use on-device models where they are good enough and privacy matters. Before launch we test on slow networks, because AI responses feel much worse on a weak connection.
How do you work with our in-house engineers and code review?
We work in your GitHub or GitLab, follow your linting and branching rules, and send every pull request through your reviewers. Architecture decisions go into short notes in the repo. If you later hire a mobile engineer in the Bay Area, they inherit the code and the context, and we help with the handover.
React Native, Flutter or native for a SaaS companion app?
If your web team writes React and TypeScript, React Native often fits, since they can read and review the code. Swift and Kotlin make sense when the app relies on background work, Bluetooth or heavy camera use. We recommend one after looking at your stack and features, and explain the trade-off in the estimate.
Who owns the code and IP when a San Francisco startup works with you?
You do. Code lives in your repositories from the first commit, and the contract assigns all intellectual property to your company, which is what investors check in due diligence. We sign your NDA and publish under your own App Store, Google Play and cloud accounts.
What does a mobile app cost for a Bay Area startup?
It depends mostly on how much backend already exists, whether AI features stream audio or video, and how many integrations the app needs. With our $25–50 per hour rate, packages start at $2,400 for a proof of concept, $9,600 for an MVP, $24,000 for a market-ready app and $48,000 for enterprise.