SFDIFYCustom mobile app development for iPhone and Android.
SFDIFY's mobile app development services take an app from idea to the App Store and Google Play, and keep improving it after launch. We build and run our own apps, including MyCheck, CostRefund and the USTAXX app, so we design for real users, reviews and updates.
Custom mobile app development services.
iPhone and Android apps
One app for both platforms from a shared codebase, so it feels native and costs less to maintain.
Flutter app development
Flutter apps like the ones behind CostRefund, the USTAXX app and the Yolda driver app.
App design and prototyping
Flows and screens tested with a clickable prototype before development starts.
Backend, accounts and payments
Sign-in, data sync, notifications and in-app payments on a backend built to scale.
AI inside the app
Features like document scanning, assistants and smart suggestions that make the app genuinely more useful.
Launch and store publishing
App Store and Google Play listings, review submission, and analytics from the first release.
From first call to launch.
Discovery
Who the app is for, the core job it does, and what a first release must include.
Design and prototype
Screens and flows tested with users in a clickable prototype.
Build and test
The app and its backend built in short cycles, tested on real iPhone and Android devices.
Launch and improve
Store release, analytics and reviews watched closely, then regular updates.
Apps we built and still run.
MyCheck
A checklist app rated 4.8 on the App Store, in 13 languages. Saves checklists from ChatGPT, Claude, Grok or Gemini.
Learn moreCostRefund
Upload Costco receipts and get an alert when a purchase may qualify for a price adjustment. Web, iPhone and Android.
Learn moreUSTAXX
The portal and app behind an IRS-authorized e-file practice. Clients ask USTAXX AI, track deadlines and follow their return in nine languages.
Learn moreYolda
The AI-native TMS for trucking. Its AI reads rate confirmations into loads, watches every CDL and medical-card date, and answers questions about your numbers.
Learn moreQuestions, answered.
What do mobile app development services include?
Usually product discovery, UX and UI design, building the iPhone and Android app and its backend, testing, App Store and Google Play publishing, and updates after launch. SFDIFY covers all of it.
Should we build native or cross-platform?
For most business apps, a cross-platform framework like Flutter or React Native gives one codebase for iPhone and Android with a native feel. Fully native makes sense for apps that lean heavily on device-specific features. Our native vs cross-platform guide covers the trade-offs.
How much does it cost to build a mobile app?
It depends on the features, platforms and backend involved. Our 2026 guide to mobile app development cost gives typical ranges by complexity.
Do you publish the app to the App Store and Google Play?
Yes. We prepare the store listings, handle review submission and set up analytics so you can see how the app is used from day one.
How do we start?
Book a free first consultation and tell us what the app should do. Projects typically start 2 to 4 weeks after the first call.
Further reading.
Mobile App Development Cost in 2026: What a Custom App Costs
Mobile app development cost in 2026: typical price ranges by complexity, the main cost drivers, MVP vs full launch, and what to budget after launch.
Learn moreNative vs Cross-Platform Apps: Which Is Right for Your Business?
Native vs cross-platform apps compared on cost, performance, timeline, and maintenance, plus when native wins and when a progressive web app is enough.
Learn moreThe Mobile App Development Process, Step by Step: What to Expect From Kickoff to Launch
The mobile app development process step by step: what happens in discovery, design, development, testing, app store launch and post-launch updates.
Learn moreMobile App Maintenance Costs: A Post-Launch Budget Guide
A post-launch budget guide to mobile app maintenance costs: what maintenance covers, how to budget for it, and which costs businesses usually miss.
Learn more