Mobile App Development
React Native-led mobile app development for startups and growing brands: one codebase shipping to both iOS and Android, and the backend built by the same team. We also take over apps another developer built.
Companies we've collaborated with
Mobile apps for iOS and Android, from first release to takeover
Most mobile work we take on starts in one of these six places.
A new app or MVP
A first release scoped around the workflow that proves the business, shipped to both app stores from one React Native codebase.
Taking over an existing app
An app another developer built that has stalled or is stuck in store review. We get it building, then stabilise it.
How a takeover works →Backend and dashboards
APIs, admin dashboards and integrations, built by the same team as the app, so nothing gets lost between vendors.
Store submission and releases
Submission, review cycles and the releases after launch. We run them, including the fixes store review asks for.
Native when it earns it
Fully native iOS and Android builds when the product needs deeper platform integration, more performance or direct device access.
AR and 3D features
Camera, 3D and augmented reality features inside an app, built in Unity alongside the rest of the product.
See our AR work →
React Native app case study: Motusi
Motusi makes engineered athletic wear and a movement analysis platform for physical therapists and performance trainers. We built the mobile app that turns raw sensor data into smooth humanoid motion in a Unity 3D viewer, running inside a React Native app that drives the interface.
The sensors were still being developed while we built, so the app had to handle their quirks in real time, including random recalibration. The platform is still in use.
Why teams bring mobile work to SLIDEFACTORY
Supporting iOS and Android with two native builds can double the cost of every release. We start from one codebase, and we say so when an app is the wrong answer.
One codebase by default
React Native ships to iOS and Android from one team, roughly one build instead of two.
The cheaper path when it fits
Some app projects are better served by a responsive web app, and we will tell you before you build.
Backend by the same team
The APIs, dashboards and integrations behind the app come from the people who build it.
Store releases handled
Submission, review cycles and post-launch releases are part of the engagement.
Taking Over an App From Another Developer
An app usually changes hands because the person who built it has moved on: a freelancer, an agency, or a cofounder who left. What tends to leave with them is the knowledge of how to build it, sign it and get it through store review.
The first job is getting the app to build from the source you hand over. Then we go through the repository, dependencies, backend connections and store status, and separate what stops the app shipping from what can wait. We stabilise first and improve second.
Red flags we look for in an inherited app
None of these means the app is a loss. They decide how long the first release takes, so we look for them first.
Accounts in someone else's name
The developer account, cloud project or repository sits under the previous developer’s login. Ownership moves before any code work.
A build that only works on one laptop
Missing signing keys, undocumented environment settings, or build steps that were never written down.
Framework versions far behind
Apple and Google raise their minimums over time. An untouched app often cannot ship an update until React Native or Expo is upgraded.
Secrets in the code
API keys or passwords committed to the repository. We rotate them and move them out of the code.
Services that no longer exist
SDKs and backend services that have been shut down or stopped receiving updates, and no crash reporting to show what breaks.
AI-generated code nobody reviewed
Screens that look finished and are not wired up to anything. Our AI code rescue work covers the patterns we find.
See AI code rescue →What to Have Ready for a Handover
Gather what you can before the first call. Gaps are common, and part of the audit is working out what can be recovered. Share access by adding us as a user, or through a password manager. Please do not send passwords or keys by email.
How we build a first release
We scope the first release around the one workflow that proves the business, ship it to both app stores, and iterate from what real users do. Our founders bring 25+ years of shipping software, which mostly buys calibration: which corners a first release can cut, and which ones stall a product two quarters after launch.
SLIDEFACTORY has been building digital products since 2018. Our studio is on SE Belmont in Portland, Oregon.
What Our Clients Say
“The Slide Factory is one of those companies you don't often have the privilege of working with. It's not just that they do high-quality work, listen to the client, meet your deadlines, and bring insights that may not have been on your radar.”
“Wow, I loved the finished product. It just worked but also I was able to go through the different iterations so easily because the guys at the Slidefactory were so professional in their process.”
“I had a fantastic experience working with Mark at The Slide Factory. He was incredibly helpful throughout the entire process, asking thoughtful questions to ensure every detail was just right.”
Frequently Asked Questions
Should I build in React Native or fully native?
React Native for most products: one codebase for iOS and Android, native interfaces, and a substantially lower build-and-maintain cost. Fully native earns its premium when you lean heavily on platform-specific hardware or need every last frame of performance. Games and AR usually belong in Unity. We build all three, so the recommendation follows your product rather than our staffing.
How much does mobile app development cost?
Scope decides it: number of user-facing workflows, backend complexity, integrations, and how much design is settled before development starts. We give a detailed estimate after a discovery conversation instead of publishing rates, and the first thing we’ll do in that conversation is look for the version of your app that costs less than the one you walked in with, a smaller v1 that reaches users sooner is almost always the better investment. If the riskiest part is technical feasibility rather than scope, a fixed-scope PoC sprint answers it before you fund the full build.
Do you work with startups?
Yes, startups are the natural fit for our cross-platform approach: both app stores from one codebase, a v1 scoped around the workflow that proves the business, and iteration from live feedback. Our founders bring 25+ years of shipping software, which mostly buys you calibrated judgment about what a first release needs.
Can you take over or rescue an existing app?
Yes. The first step is getting the app to build from the source you hand over, then we inspect the dependencies, build tools, backend connections and release status before proposing work. That may lead to a React Native or Expo upgrade, service updates, build repairs or a plan to get the app through store review. We separate what must be fixed now from work that can wait. The handover checklist on this page lists what to gather first.
Do you handle app store submission?
Yes, submission, review cycles, and post-launch releases for both the Apple App Store and Google Play are part of the engagement. We’ve been through enough review cycles to scope for them instead of being surprised by them.
What if we don't have the source code or the signing keys?
Tell us early, because it changes the plan. If the code sits in a repository the previous developer controls, the first step is getting it transferred to you. If the Android upload key is lost and the app uses Play App Signing, Google can reset the upload key through Play Console. On iOS, certificates can be reissued from your Apple Developer account. If the source code itself is gone, the options narrow to recovering what can be recovered or rebuilding, and we will tell you which once we have looked.
Will you need to rewrite the app?
Not as a first step. We stabilise what exists, get it building and back through store review, and only recommend a rewrite when fixing the app would cost more than replacing it. If that is the answer, you will hear it after the audit, with the reasons.
Do you take over apps that were built with AI coding tools?
Yes. AI-built apps have their own failure patterns, like screens that look finished but are not connected to anything, and security rules nobody asked the tool for. Our AI code rescue page covers how we audit and stabilise them.
Can you build the web side of the product too?
Yes. If the app needs a customer portal, dashboard or system behind it, see our custom web application development work. To meet the team in person, see our local app development practice. For an older product that needs a new technical foundation, see our application modernization services.
