What should you settle before hiring a mobile app development company?
Four things above all: who uses the app, on which devices, where its data comes from and who owns the Apple and Google developer accounts. What the app should do is then easier to show in a clickable prototype than in a feature list.
- Idea
- Clickable prototype
- Development
- In the App Store
Some items are not technology but business rules only you can decide. For the digital membership card of the Chamber of Architects of Baden-Württemberg in Apple Wallet and Google Wallet, the chamber decided: the card is valid for one year, renews itself and turns grey when a member leaves. On the iPhone that takes a small extra service that updates the card afterwards. Without the rule, nobody would have known it was needed.
Employee app, customer app or an app for professionals?
The answer decides login, permissions and whether the app needs an app store at all. An employee app knows every user by name, an app for customers or professionals does not.
In the field app of Hegau Energie, a utility contractor for house connections and underground cabling in southern Germany, office staff, project managers and crews from five trades work together, from underground cabling to overhead lines. Crews only see the jobs assigned to them and sign in without a password, with a code from an email or their Google account. The drug reference app of Weleda, on the other hand, is only meant for doctors, pharmacists and naturopaths. Users prove their profession through DocCheck, a login for healthcare professionals. The architecture guide of the Chamber of Architects is open to anyone who wants to explore award-winning buildings in Baden-Württemberg, in German, English and French.
Native vs hybrid: Flutter, React Native or one codebase?
For most business apps, one codebase for iOS and Android is enough, whether it is built with Flutter, React Native or web technology. Native development for each platform pays off where the app reaches deep into the device and has to respond very fast.
Weleda's drug reference app and the architecture guide have run as hybrid apps built with Cordova since 2019 and 2016, one codebase each for iPhone, iPad and Android. For Weleda this paid off twice: the app later became a desktop version in the browser without a rebuild, and texts like the privacy policy change from the server without a new release in the stores.
Does your app need to be in the App Store?
No. Many requests for an app can be met with a web app or a wallet pass, without a store listing and without review by Apple and Google. You need a store app when it has to work in the background, for example sending its location, or when customers should find it in the store.
| Approach | Example | Watch out for |
|---|---|---|
| Hybrid app in the stores | Weleda | Every new version goes through Apple's and Google's review. |
| Web app | Hegau Energie | Camera and location depend on the browser's permissions. |
| Web app in a store wrapper | Hegau Energie | Needs your own Apple and Google accounts. |
| Wallet pass | AKBW | The platform decides how it looks. |
The field app has run without a store since July 2026: crews add it to their home screen, push notifications come through the browser, and an update reaches every device at once. The wrapper for iOS and Android loads the same app and adds the device's push, camera and location. For the chamber's membership card, no member needs a new app, Apple Wallet and Google Wallet are already on their phones.
Is an app builder enough?
For a clickable prototype and the first weeks in use, yes. For running the app long term, usually not. A builder shows quickly what is needed, but then the builder's vendor decides where the data lives, which address the app runs on and who can develop it further.
We built the first version of the field app in an AI app builder. Hegau Energie had tried an off-the-shelf construction software before that did not fit its workflows. The prototype showed how it could work instead, and from May it ran with real jobs. In July the app moved to its own servers in Frankfurt: 2,656 records, 2,868 files and 21 accounts, all carried over and checked. The old version kept running until everyone had switched. Our lesson: set the day the old solution closes before you start, because every day with two systems means reconciling data by hand.
What are the phases of the app development process?
We work in six steps, and the first is a look at the data you already have.
Spreadsheets, databases, exports, documents: what already exists shows what the app really needs. For the Weleda app we asked for 16 documents before building, from indication lists to contraindications in pregnancy, and decided for each one whether it helps in the app. Only the essentials went in, as structured text instead of PDF.
Instead of a concept paper we show a clickable prototype, for Hegau Energie with jobs, plans, photos and chat. You sign off on screens as images first, then we code them. We learned that when two coded versions of a calendar failed sign-off.
After the first sprint there is a prototype on the phone, for the architecture guide already with real buildings from the chamber's database. What can wait, waits: for Weleda we deliberately left out intro screens, usage tracking and an English version.
Before every version a fixed group on your side tests it, on the iPhone through Apple's TestFlight, on Android through a test build. For every version we write down what changed. For the field app we also played through what happens without signal before launch: one page showed “0 users” instead of “no connection”, which was fixed before go-live.
Apple and Google want a description, screenshots, a privacy policy, the countries and a test account Apple can use for its review. Google Play allows only 30 characters in the app name, so the architecture guide is called “Architekturführer BW” there.
Feedback reaches us as tickets, data and files are backed up regularly. Updates come when you want something new and when Apple or Google require it.
Look at the data
Spreadsheets, databases, exports, documents: what already exists shows what the app really needs. For the Weleda app we asked for 16 documents before building, from indication lists to contraindications in pregnancy, and decided for each one whether it helps in the app. Only the essentials went in, as structured text instead of PDF.
Clickable prototype
Instead of a concept paper we show a clickable prototype, for Hegau Energie with jobs, plans, photos and chat. You sign off on screens as images first, then we code them. We learned that when two coded versions of a calendar failed sign-off.
Build in sprints
After the first sprint there is a prototype on the phone, for the architecture guide already with real buildings from the chamber's database. What can wait, waits: for Weleda we deliberately left out intro screens, usage tracking and an English version.
Test
Before every version a fixed group on your side tests it, on the iPhone through Apple's TestFlight, on Android through a test build. For every version we write down what changed. For the field app we also played through what happens without signal before launch: one page showed “0 users” instead of “no connection”, which was fixed before go-live.
Submit to the stores
Apple and Google want a description, screenshots, a privacy policy, the countries and a test account Apple can use for its review. Google Play allows only 30 characters in the app name, so the architecture guide is called “Architekturführer BW” there.
Run it
Feedback reaches us as tickets, data and files are backed up regularly. Updates come when you want something new and when Apple or Google require it.
What drives the effort?
Rarely the number of screens, mostly what sits behind them: the login, the data from your systems, offline use and the devices the app really runs on.
Weleda's drug reference app gets its data as an export from Weleda's product information system, and with every new export a script checks how many products arrive. When Weleda moved to a new system, every earlier correction to the data had to be checked again. So Weleda could compare old and new side by side, we built a second preview app with the new data.
The architecture guide had to work without signal on the road. That sounds like one line in a concept and meant: tests in airplane mode on iPhone and iPad, loading images only for the visible area, and one download package instead of three. On a construction site the devices count: on Android phones the system closed the browser while the camera was open, and the photo was lost. 11 of 16 phone users were affected, and since then the app takes photos on Android right in the page.
Who should own the Apple and Google developer accounts?
You. Whoever publishes the app needs its own organization account with Apple and Google, and we work in it as an invited developer. For the chamber's membership card this is even required: Apple only allows the issuer of a pass to sign it. Had it run through our account, every member would have had to add the card again after a later switch.
For an organization account with Apple you need a D-U-N-S number and a person with signing authority. Apple charges 99 US dollars a year, Google 25 US dollars once. Create the accounts first. With the chamber it took two tries: Apple's form silently dropped the “ü” from “Württemberg” while typing, and the D-U-N-S directory listed several entries under the chamber's name, of which Apple only accepts the headquarters. So we did the enrollment in a joint session with the chamber.
What comes after launch?
Maintenance on a schedule Apple and Google set. Both regularly require apps to target new versions of their systems, otherwise Google threatens to remove the app from Google Play.
For the architecture guide Google set deadlines on August 31, 2023, in August 2024 and on August 31, 2025, and each time we updated the app ahead of it. Then there are your own reasons: Weleda gets a release every year with new data, plus a new corporate typeface and a new logo, each version with a “What's new” text that Weleda signs off. And users ask for new things: in 2020 the Weleda app got a notes feature for every product.
How we help
We are an agency in Stuttgart, Germany, and build apps for iOS and Android, web apps and wallet passes for mid-sized companies, professional chambers and pharma. In a free first call we go through the questions above with you, and afterwards you know which approach fits your app. More about our app development.
The initial consultation is free.
Sources
- Apple: Apple Developer Program
- Apple: D-U-N-S Number
- Google: Play Console registration
- Google: Target API level requirements
Last updated: November 2026