Product & App Development

Mobile App Development Services

Mobile app development services for iOS and Android: new apps and MVPs, usually from one React Native codebase, with the backend, admin tools and store releases built by the same team. We also take over apps another developer built.

Start a Conversation Taking over an app? Start here
Motusi · React Native app with a Unity 3D viewer
Clients

Companies we’ve worked with.

What We Build

iOS and Android app development services

  • New apps and MVPs

    Custom mobile app development scoped around the one workflow a first release needs, shipped to the App Store and Google Play.

    MVP development

  • App takeovers

    Source code that has stopped building, releases stuck in review, old framework versions and projects whose original developer has moved on. We begin by restoring a working build.

    Taking over an app

  • Backends and dashboards

    APIs, account systems, integrations and administrative interfaces developed alongside the mobile application so they work as one product.

    Custom web applications

  • App Store and Google Play releases

    Submission preparation, app-review changes, release management and subsequent updates for Apple and Google’s stores.

  • Native and device-connected work

    Fully native iOS and Android development where deeper hardware access or performance is required. We also build offline-first data flows, background sync and sensor-connected products.

  • AR and 3D inside apps

    Unity-powered viewers, camera experiences and interactive 3D functionality integrated into the wider mobile interface.

    AR and 3D features
Choosing the Build Approach

React Native or native iOS and Android development

Most of our mobile app development uses React Native: one codebase with native interfaces on iOS and Android. We build fully native when the app depends on platform-specific hardware or demanding performance, and use Unity for 3D, AR and games. We recommend an approach after reviewing device needs, data flow and how people will use the app.

  • One team for app and backend

    APIs, accounts and admin tools are built alongside the app.

  • Store releases included

    Submission and review cycles for the App Store and Google Play.

  • A web app when that fits

    If a responsive web application serves the product better, we say so before the build.

    Custom web applications
Creator platform · iOS and Android

Arkh: a phone-based AR creation app for iOS and Android

From July 2020 to August 2022 we worked with Arkh’s team and partner agencies on a mobile app where people build voxel art with their fingers, place it in the real world and trade it with other users. We built the Unity experience, much of the mobile social and commerce layer, and the middleware that connects to backend services built by other teams.

  • Commerce. In-app purchases on iOS and Android, an in-app currency, limited items and redeemable rewards.
  • Device testing. Fixes for memory leaks and an Android freeze, and purchase flows tested for misuse.
  • Release. Android signing, Gradle configuration, Google Play assets and iOS entitlements.
Arkh, 2020 to 2022
About 2,600

Development hours

2020 to 2022

Engagement

iOS + Android

One app

View the Arkh project
Every Build

Included in every mobile app build

  • UX and product design

    User flows and interface design for the first release, settled before development expands. Built to WCAG when you request it, at the level you specify.

    UX & Product Design

  • Testing on real devices

    Core flows tested on target iPhones and Android phones, including offline behavior, hardware connections and store-review requirements.

  • Security and access

    Credentials kept out of the source code, and app-store and cloud access granted by role.

    AI code rescue

  • Release and support

    App Store and Google Play submission, the changes review requests, and usually one month of support after launch. On request, we hand over the completed app and its code.

Selected Work

Mobile apps we’ve built

Motusi – Advanced Motion Capture Solution
Health & fitness · React Native + Unity

Motusi – Advanced Motion Capture Solution

A React Native app with an embedded Unity viewer that turns raw sensor data into humanoid motion, built while the sensors were still in development. Still in use.

View project
All work
Taking Over an App

Taking over an app another developer built

An app can become difficult to update when the person who built it leaves. The code may still be present, but the signing keys, deployment configuration, backend access and exact steps for a store release are scattered across accounts and old laptops. We try to reproduce the build from the source provided, then inspect dependencies, backend connections, store status and the issues blocking release.

We separate immediate stability work from improvements that can follow. A rewrite is considered when replacing the existing code is the more reasonable path, with the recommendation made after review.

AI code rescue

  • Red flags in an inherited app

  • Store accounts in someone else’s name

    Ownership and administration access need to be established before signing or publishing new builds.

  • A build that runs on one laptop

    Certificates, environment variables or undocumented settings may be missing from the shared project.

  • Framework versions too far behind

    An old React Native, Expo or native build configuration may no longer match current store requirements.

  • Credentials inside the source

    We identify secrets that should be rotated and moved out of committed code.

  • Services that have disappeared

    SDKs, APIs or third-party systems may have been retired without a replacement path, sometimes with little crash-reporting visibility.

  • AI-generated code without review

    We look for missing integrations, access controls and tests in code assembled using AI tools.

What to have ready for an app handover

If another developer built the app, gather what you can. We can start on what is missing while access comes together. Add our team as users or share through a password manager. Please do not email passwords, tokens or signing keys.

Source repository. GitHub, GitLab or Bitbucket access, with commit history when available.

App-store accounts. Team access to App Store Connect and Google Play Console.

Signing material. Android upload key and password, iOS certificates and provisioning profiles, where available.

Backend and hosting. Cloud-console, database, API and Firebase project access as appropriate.

Third-party services. Payment processing, login providers, notifications, analytics and crash reporting.

Domains and DNS. Access to any domains, deep links or web services used by the application.

Design and documentation. Design files, architecture notes, handover documents and previous ticket history.

Previous development agreement. The paperwork that establishes ownership of the code and relevant accounts.

How We Build a First Release

How we build the first release of a mobile app

UX & Product Design
  1. 01

    Define the first release

    We identify the task the customer must be able to finish, what data it requires and how the app will behave. MVP development is an option when feasibility needs testing first.

  2. 02

    Build app and backend together

    React Native or native interfaces are developed alongside the APIs, accounts and integrations they depend on. Interfaces are built from the approved designs.

  3. 03

    Test on actual devices

    We test the core flows across target phones, with attention to hardware, offline behavior and store-release requirements. Then we manage submissions to Apple and Google.

  4. 04

    Support the release

    We usually provide one month of post-launch support. OS updates, maintenance and new features can continue after the initial period.

Client feedback

What clients say about working with us

“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.”
Peter Kirwanmebot.ai★★★★★Read on Google ↗
“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.”
Chris ArendsCasl Systems★★★★★Read on Google ↗
“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.”
Leisa RaymondScarlet Ibis Bookkeeping★★★★★Read on Google ↗

Mobile app development in Portland, Oregon

SLIDEFACTORY’s studio is at 4520 SE Belmont St, Suite 300. As Portland app developers, we meet teams from Portland, Beaverton, Hillsboro, Sherwood, Gresham and Vancouver, Washington, in person for discovery and key build reviews.

We also work with clients nationally. Remote reviews run on working builds installed on your own phones, so decisions are made on the app itself.

FAQs

Questions about mobile app development services

Should we use React Native or fully native development?

React Native serves most iOS and Android products through one shared codebase. Fully native code is useful when the app needs deeper operating-system integration or performance. We choose based on what the product needs to do on the target device.

How much does mobile app development cost?

Cost depends on screens, user workflows, integrations, backend features, hardware, offline requirements and release scope. We prepare a written estimate after discovery. If one technical assumption remains uncertain, a proof of concept can address it first.

Do you work with startups building their first app?

Yes. We help define a first release around one workflow that customers can use. We can build the mobile application, its supporting backend and administrative tools, then manage submission to both app stores.

Can you take over an existing app that is stuck?

Yes. We first get the application building from the available source, inspect repository and dependencies, check backend access and identify what prevents store submission. That becomes the basis for a stabilization plan.

Do you handle Apple App Store and Google Play submission?

Yes. Our iOS app development work includes submission, review cycles and fixes requested during store review. We also prepare Google Play releases and post-launch updates.

What if the source code or signing keys are missing?

If the Android app uses Play App Signing, Google can reset a lost upload key through Play Console. iOS certificates can be reissued from the client’s Apple Developer account. If the source code is missing, we assess what can be recovered and whether rebuilding is necessary.

Will you rewrite our existing app?

We inspect it first. If the current structure is sound, stabilizing the build and updating the necessary components may be the right approach. A larger replacement is recommended only after comparing the condition of the code with the cost and risk of repairing it.

Can you repair an app built with AI coding tools?

Yes. We review the actual functions, code paths, dependencies, access controls and tests. Where the issues involve missing verification or security, we can apply our application modernization and AI code rescue process.

Can you build the website or web dashboard too?

Yes. The same team builds APIs, dashboards, account tools and supporting web applications. See custom web applications.

What happens after launch?

Support is usually provided for one month after release. Ongoing maintenance, operating-system changes and product development can be arranged afterward. We can hand over the completed app and its code on request.

Work With Us

Tell us about the app and where it is stuck.

A new mobile product, an application you need to take over or a platform decision that is still open. Tell us where things stand, and we can explain where we would begin.

Start a Conversation 4520 SE Belmont St, Suite 300
Portland, Oregon