Mobile app development in Miami
If your Miami company sells into Latin America, a good share of your users will open the app on a mid-range Android phone on a mobile connection that drops. An app designed on the newest iPhone over office wifi will feel slow there, and a payments app that feels slow feels unsafe.
We build in React Native, and we build our own product, Amour, Android first, so we are used to testing where users actually are. That means keeping the bundle small, caching what can be cached, making every money action safe to retry when the network cuts out halfway, and showing a clear pending state instead of a spinner that never ends. Fingerprint and face sign-in use the phone's own secure hardware, and sessions live in the device's secure storage rather than in plain app storage.
Miami's software buyers tend to face south. Many of the companies that set up here in the last few years came for the same reason: it is where a US-incorporated business can sit next to its Latin American customers, investors and staff. Cross-border payments, remittances, neobanks, crypto infrastructure and the US arms of Latin American companies make up a large part of the local technology market, alongside real estate, hospitality and trade. The systems they need are rarely built for one country.
That shapes the work. Money movement is the core of the product rather than a feature bolted onto it: idempotent payment calls, a double-entry ledger, reconciliation jobs that compare your records against a partner's settlement file every night and flag the difference. The product has to handle Spanish and Brazilian Portuguese properly, validate local ID numbers and address formats, and settle through rails such as Pix in Brazil and SPEI in Mexico as well as cards. Crypto products add wallets, chain indexers and custody integrations, and the same principle applies: your database has to agree with the chain, and when it drifts, somebody needs a report saying where. Real estate, hospitality and trade bring their own version of the problem, usually a workbook that runs the business and quietly disagrees with its copies.
The hiring market has moved with the migration of finance and technology firms from New York and California. Built In puts the average base salary for a software engineer in Miami at around $145,000, and engineers who are bilingual and have shipped payments work are the hardest seat to fill. That is the seat we fill for a defined build: a payments integration, a reconciliation system, a second-country launch, or the months while a permanent hire is found. Work starts with a fixed-price two-week piece, and the code belongs to you from the first commit.
We move our working day for Florida. Four hours of every working day overlap with your morning in Eastern time, stand-up included, so calls, code review and decisions happen live with the engineer who writes the code. Everything else is written down where you already work, and runbooks and architecture notes are written as we go, so the next engineer who joins can read how the money moves.
We are the right fit for a defined build: a payments integration, a reconciliation system, a second-country launch. Senior capacity starts within days, the first piece is a fixed-price two-week engagement, and we can cover the months while a permanent hire is found. Agencies serving Miami's fintech, hospitality and retail brands can put the work under their own name.
Four ways this arrives.
And crashes on the ones your users own. We add crash reporting with readable stack traces, find the handful of devices and OS versions causing most of the crashes, and fix those before anyone touches a feature.
Signing keys on a laptop, a manual build, store notes written at midnight. We move builds and signing into CI, add over-the-air updates for JavaScript-only fixes, and write down exactly how a release goes out.
A Bluetooth device, a vendor SDK, a camera pipeline, a background task the OS keeps killing. We write the native module in Swift and Kotlin, expose a small typed interface to React Native, and keep it isolated so upgrades stay possible.
Forms that vanish, actions that send twice. We decide what must work offline, keep it on the device, queue writes with idempotency keys the backend understands, and show the user plainly what is still waiting to sync.
Our own React Native app on Android, with retraction built into the client because moderation can pull a message after it has been sent.
Read the write-up →Asked by Miami teams.
How do you work with teams in Miami?+
We are in Bengaluru and move our working day for Florida, so four hours of every working day overlap with your morning in Eastern time, stand-up included. Calls, code review and decisions happen in that window. Everything else is written down in your own tools, whether that is Slack, GitHub or Linear, and the person on every call is the engineer who writes the code.
Can you build for Latin American markets as well as the US?+
Yes, and it is more than translation. Mexican and Argentinian Spanish differ, Brazilian Portuguese is its own language, and ID numbers, address formats, currencies and instalment payments all change by country. We design localisation into the first component, format money through the platform's own internationalisation tools, and integrate the payments provider you have chosen, with room for a second provider and local rails such as Pix and SPEI.
How does your rate compare to hiring in Miami?+
Built In puts the average base salary for a software engineer in Miami at about $145,000, before equity and benefits. Our published rate is $35/hour, or $5,400 a month for an embedded engineer, with a $5,000 minimum. There is no recruiting time and no employment overhead, and work starts within days of the call. The first piece is a fixed-price two-week engagement at $2,800, so you judge us on working code.
Can you work white-label for a Miami agency?+
Yes. Miami agencies regularly win fintech, hospitality and ecommerce projects that need more engineering than the in-house team can take on at once. We work under your name as part of your team, so your client deals with you and the work arrives as yours. The NDA comes before any specifics, the code belongs to the client from the first commit, and runbooks and architecture notes are written as we go.
React Native or fully native?+
React Native for most products: one codebase, one team, both stores. Fully native makes sense when the app is mostly the hard native part, such as heavy camera or audio processing, complex background work, or a platform feature React Native does not support yet. We will tell you which side of that line you are on, and write the native parts by hand either way.
Expo or bare React Native?+
Expo, in almost every case now. Development builds and config plugins removed most of the old reasons to eject, and EAS handles builds and signing. We go bare only when a native dependency genuinely cannot live inside a config plugin, and we will explain why before doing it, because it makes every future upgrade more work.
Can you take over an app someone else built?+
Yes. We start by getting it to build on a clean machine, which is often the hardest step, then bring React Native and its dependencies up to a supported version before adding features. We tell you what state the app is in, including where the store listings, signing keys and accounts actually live, before quoting anything larger.
Who handles App Store and Play Store submission?+
We do, from your developer accounts, not ours. We prepare the builds, the privacy disclosures and the notes for the reviewer, and deal with rejections when they come. The accounts, signing keys and listings stay in your name, so you can change developers later without asking anyone's permission.
Does our backend need to change for a mobile app?+
Often, a little. A mobile client stays on old versions for months, retries on bad networks, and cannot be fixed by a server deploy. That means versioned endpoints, idempotent writes, and a way to tell an old client it must update. We check the backend for those before the first screen is built, because retrofitting them after launch is slower.