Mobile app development in Chicago
Field apps in the Midwest get used in cabs, yards and warehouses with patchy signal and gloves on. A driver capturing proof of delivery, a technician logging an inspection or an adjuster photographing damage needs an app that works offline, uploads when it can, and never loses a photo because the connection dropped halfway.
We build those apps in React Native, with offline queues on the device and uploads that resume rather than restart. Photos go straight to storage with a presigned URL, the same pattern we use in our own app, Amour. Sign-in uses the phone's built-in fingerprint or face unlock, so a driver can get in quickly between stops, and the app shows plainly which captures are still waiting to upload, so nobody drives off wondering whether the proof of delivery went through.
Chicago's software buyers are mostly not startups selling to other startups. The city's economy rests on trading and derivatives, around CME Group and the proprietary trading firms that grew up beside the exchanges; on freight and logistics, because this is where much of the country's rail and trucking traffic meets; on insurance, from carriers to the brokers and agencies around them; and on manufacturing and distribution across the Midwest. These are established, profitable businesses, and a good deal of their software is older than some of the engineers who maintain it.
So the work is integration and modernisation more often than a blank page. Freight systems speak EDI and carrier APIs that disagree about what happened to a load. Insurers run on policy administration systems nobody wants to replace and everybody wants to build around. Trading firms keep their latency-critical code with in-house specialists, and buy the layer around it: risk and reconciliation reports, operations dashboards, internal tools and data pipelines. The strongest pitch in Chicago is rarely a rewrite. It is a clean, documented system built beside the old one, with work moved across one piece at a time.
Built In puts the average base salary for a software engineer in Chicago at around $133,000, and every employer in the city competes with the trading firms for the same engineers. The result is a familiar backlog: the carrier integration that has to be done properly once, the agency portal everyone complains about, the internal tools the engineering team is too busy to reach. Those are defined pieces of work, which suits an engagement. It starts with a fixed-price two-week piece, and the code belongs to you from the first commit.
We move our working day for Illinois. Four hours of every working day overlap with your morning in Central time, stand-up included, so calls, reviews and decisions happen live with the engineer who writes the code. Everything decided or discovered is written down in your repository and tracker, and runbooks and architecture notes are written as we go, so the system built beside the old one is documented from its first day.
We are the right fit for a defined piece of modernisation, an integration that has to be done properly once, or the internal tools your own engineers are too busy to reach. Senior capacity starts within days, the first piece is a fixed-price two-week engagement, and agencies serving Chicago's insurers 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 Chicago teams.
How do you work with teams in Chicago?+
We are in Bengaluru and move our working day for Illinois, so four hours of every working day overlap with your morning in Central time, stand-up included. Calls, reviews and decisions happen in that window. The rest of the work lives in your tools: messages in Slack, code in GitHub, tickets in Linear. The person on every call is the engineer who writes the code, so a question about the system gets answered by the person who built it.
Do you build for Chicago freight and logistics companies?+
Yes. The work is usually the layer that turns messy events into a shipment you can trust: EDI load tenders, status updates and invoices parsed into one event model, carrier tracking APIs reconciled against it, and proof-of-delivery photos from a field app that works offline. Around that sit the operations screens a brokerage floor uses all day, and the pipelines that turn loads and lanes into pricing and margin reports.
How does your rate compare to hiring in Chicago?+
Built In puts the average base salary for a software engineer in Chicago at about $133,000, before benefits and bonus, and you are competing with trading firms for that person. 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. A fixed-price two-week first piece at $2,800 lets you judge us on output.
Can you build alongside our existing systems rather than replacing them?+
Yes, and in Chicago that is most of the work. We read the old system, write down what it actually does, and build the new piece beside it. Work moves across one workflow at a time, with both running until the last piece lands, so the business keeps running without a cut-over weekend. We did exactly this on FM360, moving a pipeline across module by module rather than in one cut-over.
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.