Services · Fintech Apps

Fintech apps built by a team that runs its own.

SFDIFY is a fintech app development company. We build and run money software of our own: USTAXX, a tax filing portal and app from an IRS-authorized e-file provider; CostRefund, which watches Costco receipts for price drops; and the settlements and bonus payouts inside Yolda. We bring that experience to fintech products for clients.

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Tax, payments and payoutsiPhone, Android and webSecurity built in from day oneFree first consultation
What we build

Fintech software development services.

Secure client portals

Encrypted document upload, e-signature, status tracking and private messaging, like the USTAXX portal.

Tax and accounting apps

Filing flows, document checklists, deadline countdowns and preparer review tools.

Payments, billing and payouts

Subscriptions, invoices and payouts with Stripe and other providers, including earned pay sent to a bank.

Receipt and document AI

Receipts, statements and tax forms read by OCR and AI into structured, checkable data.

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Personal finance and savings apps

Consumer apps that watch prices, spending or deadlines and alert people at the right moment, like CostRefund.

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Admin, audit and support tools

Staff consoles with roles, audit trails and the views your support and compliance teams need.

Case study · USTAXX

USTAXX: tax filing rebuilt as a portal and an app.

The problem

Tax clients send documents as photos, PDFs and emails, often in their second language, and rarely know what is still missing or where their return stands.

What we built
  • A secure client portal, an iPhone and Android app and a staff admin
  • Encrypted uploads and return PDFs behind Face ID
  • Form 8879 e-signature
  • OCR that sorts uploads into the right return
  • Deadline countdowns and USTAXX AI, in nine languages
How it works today

Clients upload, sign and track their return in their own language, and preparers work from one record, for an IRS-authorized e-file provider serving all 50 states.

See USTAXX
Is this a fit?

When to hire us, and when not to.

A good fit when

  • ✓You are building a product that handles money, tax, payments or financial documents.
  • ✓Customers need to upload sensitive documents and see where things stand.
  • ✓You want a mobile app and a web portal that share one secure record.
  • ✓You need payments, billing or payouts wired into the product.

Probably not a fit when

  • ×You need a licensed bank, broker or money transmitter. We build the software, not the license.
  • ×You need a compliance certification on its own, with no software to build.
  • ×An existing fintech platform already does exactly what you need.
How we work

From first call to launch.

01

Map the money flow

Who pays, who gets paid, which documents move, and the rules around each step.

02

Design for trust

Flows, permissions and security agreed before building, with your compliance advisers involved.

03

Build and test

The app, portal and backend built in short cycles and tested with real scenarios.

04

Launch and improve

Store releases, monitoring and support tools in place, then improvements from real use.

Cost and timeline

What drives the cost of a fintech app.

Fintech apps cost more than typical apps because of security and integrations. These factors matter most.

Payment and banking providers

Each provider such as Stripe, a bank data API or a payout service adds integration and testing.

Security requirements

Encryption, access controls, audit trails and device security add design and review time.

Platforms

A web portal, an iPhone app and an Android app sharing one backend is more work than one of them.

Document processing

Reading receipts, statements or tax forms reliably needs OCR, AI and a test set of real documents.

Regulation

Rules for your product, set with your legal and compliance advisers, shape flows, records and retention.

For how app budgets are built, read how much an app costs to build.

Proof

Money software we built and still run.

USTAXX

The portal and app behind an IRS-authorized e-file practice. Clients ask USTAXX AI, track deadlines and follow their return in nine languages.

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CostRefund

Upload Costco receipts and get an alert when a purchase may qualify for a price adjustment. Web, iPhone and Android.

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Yolda

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 more

Segeo

Writes and publishes a useful blog post to a business's site every day and runs its Instagram. SaaS from $89 a month.

Learn more
FAQ

Questions, answered.

What does a fintech app development company do?

It designs and builds software that handles money: payments, billing, payouts, tax, accounting, savings and the secure portals and documents around them. SFDIFY builds and runs fintech products of its own, including USTAXX and CostRefund.

Do you handle compliance?

We build with security practices such as encryption, access controls and audit trails, and we design flows with your legal and compliance advisers. We do not provide legal advice or hold financial licenses for clients.

Which payment providers do you work with?

Stripe for subscriptions, invoices and payouts, which we run in our own products, and other providers where your product needs them.

Can you build both the app and the web portal?

Yes. USTAXX has a web portal, an iPhone and Android app and a staff admin, all sharing one record. We build the same way for clients.

Can AI read receipts and financial documents?

Yes. CostRefund reads Costco receipts and USTAXX sorts uploaded tax documents with OCR and classification. We test accuracy on real documents before launch.

How do we start?

Book a free first consultation and describe the money flow your product needs. Projects typically start 2 to 4 weeks after the first call.

From the blog

Further reading.

Product

How Much Does It Cost to Create an App? A Step-by-Step Estimate

How much does it cost to create an app? Estimate it step by step: app tiers, team choice, native vs cross-platform, maintenance and AI features.

Learn more
Product

How to Hire App Developers for a Business App

Choose between a freelancer, in-house team, or app development studio to build your business app.

Learn more
Engineering

Native 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 more
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