App integration means your app exchanges data with the software you already use, such as your CRM, scheduling, stock or accounting system. That almost never happens directly. There's a layer in between: your own server that lets the app and your systems talk to each other securely.
Without integration, an app quickly becomes an island. Staff retype things, customers see outdated information and mistakes creep in. In this article you'll learn how a good integration is set up, which choices you make and what to watch out for.
Why you connect an app to your existing software
An app only becomes truly useful when it works with up-to-date data. A few examples from small and medium-sized businesses:
- A customer books an appointment in the app and it goes straight into your employee's calendar.
- A mechanic closes a job sheet in the app and the invoice is ready in your accounting software.
- A customer sees their orders and invoices from your CRM in the app.
- An employee checks current stock in the app before promising anything.
- An order from the app goes straight through to your kitchen or warehouse.
Every integration saves duplicate work and prevents mistakes. The question isn't whether to integrate, but how.
How app integration with your systems works
An app you publish on the App Store or Google Play runs on your user's phone. You don't want to put passwords or keys for your accounting software or CRM in there. Someone with a bit of technical knowledge can extract them from an app. That's why a good setup looks like this:
- The app: what the user sees and uses.
- Your own backend: a server of yours that decides who can see and do what. The app only talks to this server.
- The integrations: the backend talks to your CRM, scheduling, accounting or stock system through an API. An API is an agreed way for two programs to exchange data.
That middle layer has more advantages. If you later switch accounting packages, you only change the backend and the app doesn't need to go through the app stores again. Read more about how an API works in our article on having an API integration built.
Which systems can you connect to an app?
In principle, any system that has an API. That's true for most modern software. Common integrations are:
- CRM: customer details, contact history and appointments.
- Accounting: invoices, payments and outstanding items. See also our article on connecting your accounting software.
- Scheduling and calendar: available times, rotas and appointments.
- Stock and webshop: products, prices and availability.
- Payment provider: payments and refunds.
- Email and messages: confirmations, reminders and push notifications.
Does an old system have no API? Then there are sometimes other routes, such as exchanging files or working directly with the database. That is more fragile, though. Sometimes it's smarter to replace the old system.
Live data or syncing?
An important choice: does the app fetch data live every time, or does the backend keep its own copy that's updated regularly?
- Fetching live: always up to date, but the app depends on the speed and availability of your other system. If that's down, the app doesn't work either.
- Syncing: the backend keeps a copy and updates it, for example every few minutes or as soon as something changes. The app is faster and keeps working if another system briefly falters.
- Notifications from the system: a lot of software can send a signal itself when something changes. Then the backend doesn't have to keep asking whether there's anything new.
A combination is often best: syncing for data that rarely changes, such as products, and live for things where every second counts, such as available appointments. Does your app also need to work without signal? Then read how to set up an app that works offline.
What to watch out for with app integration
- Decide which system is in charge of each piece of data. Does a customer address come from your CRM or from the app? Two sources for the same data leads to confusion.
- Limit what the app can do. A customer only sees their own data, an employee only what relates to their work.
- Allow for limits. Many systems restrict how many requests you can make per minute.
- Log what happens. If an integration fails, you want to know what went wrong and what needs to be redone.
- Send an alert on errors, so someone picks it up before customers notice.
- Think about the GDPR (AVG in Dutch). Don't pull more personal data into the app than needed, and record which parties you share data with.
How to tackle app integration step by step
- List all the systems you use and what data they hold.
- For each screen in the app, decide which data is needed and which system it comes from.
- Check for each system whether there's an API and what it can and can't do. Ask your supplier for the documentation.
- Choose for each piece of data: fetch live or sync.
- Test the integration first with a test environment or test data, not with your real records.
- Agree who monitors and maintains the integration once the app is live.
Common mistakes with app integrations
- Putting API keys in the app itself instead of on your own server.
- Only thinking about integrations when the app is almost finished.
- Not testing with real volumes of data, so the app slows down as soon as it goes live.
- No plan for what happens when a connected system gets an update and its API changes.
App integration by Violexa
At Violexa we build apps with their own backend, so integrations are secure and easy to maintain. We first look at which systems you use and which data is really needed in the app. Read more about web applications and software. A custom app or web application starts from €1,799 excl. VAT (€2,177 incl. VAT) per project. If you want integrations to keep working after updates to other software, that's possible with a maintenance package, from Silver at €179 excl. VAT (€217 incl. VAT) per month.
Curious how your app and systems could work together? Book a free quickscan. In 30 minutes, online or at your location, we discuss your situation. Afterwards you get short written advice with a price indication, with no obligation.
Frequently asked questions
Can I connect my app to my CRM?
Yes, if your CRM has an API, and that's true for most modern packages. The integration then runs through your own server, which decides which customer data the app can see. That keeps your access keys out of the app.
Why does an app need a backend?
The backend is a server that sits between the app and your other systems. It stores access keys securely, checks who is allowed to do what and catches errors. You can also change the backend without publishing a new version of the app in the stores.
What if my software has no API?
Then there are sometimes other ways, such as exchanging files or working directly with the database. Those solutions are more fragile and need more maintenance. Sometimes replacing the old system is cheaper in the long run.
How up to date is the data in an integrated app?
That's up to you. Data can be fetched live or synced regularly. For available times or stock you usually choose live; for data that rarely changes, syncing is faster and more reliable.
