What it can include
- Feasibility check
- Before quoting, we review the other system's API documentation, access rules and plan requirements, and tell you what is and is not possible.
- Booking and scheduling systems
- Read availability, create and change bookings, and sync customer details where the provider's API allows it.
- E-commerce platforms
- Products, stock, customers and orders from platforms such as Shopify and WooCommerce.
- Payments
- Deposits, prepayments and checkouts through providers such as Stripe, with sensitive card data handled by the provider.
- CRM and email tools
- Sync contacts and consent preferences so your marketing and customer records stay consistent.
- Secure middle layer
- A small back end where needed, so secret keys never sit inside the app and calls can be cached, logged and rate-limited.
Why integrations matter
Most small businesses already rely on several systems: a booking tool, an online shop, a point-of-sale system, a CRM or a mailing list. A mobile app is far more useful when it works with those systems instead of creating another place where data has to be maintained. When a customer books in the app, the booking should appear in the diary your staff already use. When they buy, the order should land in your shop's back office.
API integration is how that happens. Apptavio builds iPhone and Android apps that connect to your existing software through official APIs, and we check what is realistic before you spend money.
Who this is for
- Businesses that already use a booking, shop, POS or CRM system and want an app on top of it.
- Businesses with an existing app that needs to connect to a new or changed system.
- Businesses with a custom-built back end that needs a mobile front end.
What we typically integrate
Booking and scheduling software
Availability, bookings, cancellations and customer records. Many booking providers offer APIs, but access rules vary: some limit them to partners, some to particular plans, and some do not allow creating bookings from third-party apps.
E-commerce platforms
Products, variants, stock, customers and orders. Shopify and WooCommerce both document APIs used for custom apps and storefronts.
Payments
Deposits, prepayments and checkouts through payment providers such as Stripe. Card details are collected by the provider's secure components, so they never touch our servers or yours.
CRM, email and loyalty tools
Contact details, consent preferences, loyalty balances and segments, so the app and your marketing tools agree on who opted in to what.
Your own systems
Garage management software, membership databases, job-tracking tools or bespoke systems — provided there is an API or we can agree a safe way to add one.
How we approach an integration
- Discovery. We list exactly what the app needs: for example "read available slots for service X, create a booking, cancel a booking".
- Feasibility check. We read the provider's documentation and terms, confirm which plan or permissions are required and, where possible, test with a sandbox account.
- Architecture. For most integrations we place a small, secure back end between the app and the provider. It holds secret keys, handles authentication, caches data to keep the app fast and protects you from hitting rate limits.
- Build and test. We handle the unhappy paths — the provider is down, a slot has just been taken, a payment fails — so customers see a clear message rather than an error.
- Monitoring. After launch we watch for failures and keep up with API changes, which providers announce from time to time.
See your app before you buy
You can see a free, personalised, interactive concept of your app built from your existing website before any integration work starts. It shows how booking, shopping or account screens could look with your branding and content. Data in the concept is illustrative and nothing connects to your systems yet — that is exactly what we scope next. A person reviews every concept before it is sent, and there is no obligation.
What affects the cost
Integration work is quoted as part of a custom app project, which starts from €1,499 (indicative starting price). The main factors are:
- API quality — clear documentation, sandbox accounts and stable versions reduce effort considerably.
- Number of operations the app needs.
- Authentication — simple API keys versus OAuth flows or per-customer sign-in.
- Back-end requirements — caching, webhooks, background sync and logging.
- Error handling and edge cases specific to your business rules.
- Ongoing changes — providers update their APIs, so integrations need maintenance.
Honest limitations
- We can only integrate what the provider allows. If an API does not support an action, we cannot add it from outside. We will tell you early.
- Some APIs cost extra or require a particular plan. Those fees are paid to the provider.
- Providers change their APIs. Most give notice, but integrations need monitoring and occasional updates.
- Your data stays subject to your providers' terms and data-processing agreements, which you should review as the data controller.
- We do not use unofficial methods, such as scraping a web interface, because they are fragile and can breach the provider's terms.
Frequently asked questions
What is an API?
An API (application programming interface) is a documented way for one piece of software to request data or actions from another. If your booking system has an API, your app can ask it for available times and create a booking without anyone copying data by hand.
How do I know if my software has an API?
Look for 'API', 'developers' or 'integrations' in your provider's website or help centre, or ask their support. We are happy to check for you as part of the scope call. Some providers only offer API access on higher plans or to approved partners.
What if my system has no API?
We will tell you before you commit. Options include switching to a system with an API, using a supported export or webhook, or building a dedicated back end for the app. We do not recommend screen-scraping or unofficial methods, because they break easily and may breach the provider's terms.
Is integrating with my systems secure?
We follow the provider's recommended authentication, keep secret keys on a server rather than inside the app, request only the permissions the app needs and use encrypted connections. Your providers' own security and data-processing terms also apply.
How much does an integration cost?
It depends on the quality of the API documentation, the number of operations needed, authentication, error handling and whether a middle-layer back end is required. Integrations are quoted as part of a custom app project, which starts from €1,499 (indicative starting price).
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Last updated 16 October 2026