What is Appsemble?

Appsemble is a platform with which (PWA) apps can easily be developed. Someone with little technical knowledge should be able to easily create apps with this. Someone with a lot of technical knowledge can create complex apps and therefore saves time by reusing building blocks. Appsemble has been developed with the following principles:

● Open Source, no vendor lock-in.
● Use of modern standards (PWA, React / Node.js, Docker, Kubernetes, Oauth2, JWT)
● Pragmatic: prefer minimal functionality today than a fantastic app tomorrow. We iter it further every day.
● An app is built by creating an app recipe in a human-readable (YAML / JSON) format. Building blocks are selected and configured in this.
● Apps must be easy to share, copy and adapt.
● Graphic choices are independent of the app and are defined at the organizational level.

What is PWA?

The progressive web app (PWA) is one of the newest developments in the field of apps. A PWA connects the properties of a website with many features of native mobile apps. As a result, the application functions independently of the operating system and at the same time as a website and app.

What is Open Source?

The source code of open source software is free. This means that it is available and adaptable. Open source software is attractive for developers and system administrators around the world. They can make improvements to the source code of open source or work on all kinds of extensions that benefit the community.

What is vendor lock-in?

Vendor lock-in makes a customer dependent on a supplier for products and services because he is unable to change suppliers without substantial switching costs or inconvenience. Appsemble does not apply this way of doing business and deliberately does not create a vendor lock-in. We want customers to choose us as long as we continue to add value. With the maturing of the Appsemble ecosystem there will undoubtedly be several providers offering services.

What is Appsemble CE?

Appsemble CE (community edition) is 100% open source code and can be downloaded at

What is Appsemble EE?

Appsemble EE (enterprise edition) is a set of functionalities aimed at Enterprise users. This code is public, but not open source. A license must be purchased for it. Prices are not yet known. This is because no premium functionalities have yet been built: all functionalities are currently being released 100% open source in Appsemble CE.

What is Appsemble SAAS?

Appsemble SAAS (Software as a Service) is the possibility to use Appsemble without having to set up your own hosting.
In addition to hosting with an SLA, support is also provided.
There is also access to a partner network (for example for logging in to DigiD, eHerkenning or certified hosting)

What does Appsemble SAAS cost?

The cost per app are € 50 ex. VAT per month. This includes:

  • Hosting in the European (GDPR compliant) cloud.
  • Standard Appsemble backend.
  • 10GB storage.
  • Standard SLA.

When you need more than 10 apps, please contact us for a better price.

Are there SAAS options for organisations?

SAAS hosting with an Enterprise SLA is gets you the following extras compared to the standard app costs:

  • Faster response time for support.
  • Technical support for developers.
  • Greater amounts of users or data.
  • Additional hosting of custom backends.
  • Support in connection with single-sign-on setup.

Costs per app are € 100 ex. VAT per app.

When you need more than 10 apps, please contact us for a better price.

What is a building block?

Building blocks are pre-programmed functionality blocks, with which you build your own application. Because you use pre-programmed blocks you do not have to be able to program yourself to make the app.
Depending on the building block, a number of simple settings can be made per building block.

What does it cost to make a building block?

Making a building block yourself naturally costs nothing. Technical knowledge is required. Appsemble B.V. can develop building blocks at the following target prices:

● Small block (no external dependencies): from € 1000,-
● Large block (link with external services): from € 2500, –

The blocks will be published open source and maintained for at least 6 months by Appsemble B.V. If the blocks are not interesting enough for the community to maintain, a maintenance agreement will have to be concluded after that time, prices on request.
If the blocks must remain the private property of the client, the prices are on request.

What does it cost to make an App?

Creating an app yourself based on our standard building blocks costs nothing. If the desired app requires additional building blocks that have not yet been developed, these are the target prices to be used by Appsemble B.V. to make:

● Small app (incl. 1 or 2 extra building blocks): from € 5000, –
● Medium-sized app (about 4 extra building blocks): from € 10,000
● Large app (more than 4 extra building blocks and a customized backend): from € 25,000

The app recipes will be published open source and maintained for at least 6 months by Appsemble B.V. If the app recipes are not interesting enough for the community to maintain, a maintenance agreement must be concluded after that time, prices on request.
If the apps must remain the private property of the client, the prices are on request.

Can I keep my app closed?

Sure. Even though the Appsemble platform itself is open source, it’s allowed to create your own blocks or app and keep it private (closed).

Hybrid models are also possible. For example, develop new blocks as open source, but keep the app built with those blocks closed. These aspects can be closed:
– Specific combination/configurations of blocks in your app (the app recipe)
– Specific branding (theme) of the app
– The data/contact of the app

This balance should result in a health ecosystem with shared blocks even though it can result in unique apps.

Terms and Conditions

Our terms and conditions.

Municipalities and Common Ground

What is OpenApps?

OpenApps gives municipalities the opportunity to build apps themselves without programming. Unlock your data in an app: fast, cheap and open source.

The OpenApps initiative was launched at the end of 2018 as a partnership between Appsemble B.V. and the municipality of Amsterdam with the aim: co-creation to stimulate the joint development and sharing of apps for the municipality of Amsterdam and all other municipalities in the Netherlands.

In 2019, interest quickly emerged from a number of larger municipalities abroad, Dutch government institutions and the healthcare sector. Further partnerships are being explored.

Together with several larger municipalities in the Netherlands and the VNG (Association of Dutch Municipalities), we are exploring how we can further shape OpenApps (for example as a foundation) for anchoring continuity and the vendor lock-in promise.

What is the relationship between Appsemble and OpenApps?

The apps initiated by OpenApps have until now been issued as a commercial assignment to Appsemble B.V. The end result is open source and is added to Appsemble CE.
This is a pragmatic choice because Appsemble is the co-founder of OpenApps and has the required expertise in-house.

What does membership of the OpenApps consortium cost?

This will vary per municipality. We want to keep OpenApps accessible for every municipality, large or small. That is why the number of inhabitants per municipality will be considered. There is a maximum amount of € 5000 per year, this pays a large municipality such as Amsterdam.

What does membership of the OpenApps consortium offer?

● Knowledge sharing session 3 – 4 times a year.
● Use apps developed by other consortium members.
● Subscription money is spent on further development of the Open Source platform, building blocks and Apps.

Will OpenApps become part of VNG Common Ground?

We investigate where we can connect to the Common Ground movement. We seem to fit into the “layer architecture”.
Not all common ground layers are already available in practice.
Appsemble CE has its own implementation for this. Any layer could be replaced in the future.
We are an open platform anyway and work easily with external APIs.


Becoming a partner

The best Apps are created by a local partner that understands the Appsemble low code platform and can implement custom solutions when needed.
The concept is pretty simple: you help Appsemble to become the no. 1 open source, low code platform, we help you in becoming a successful app builder for your local community.

The advantages:

  • Access to an Appsemble account manager.
  • Obtain local leads.
  • 100% commission on hosted services.
  • Free technical support when you’re building open source components.
  • Discounted fee on technical support when you’re building close source components.


How to enable webcam recordings in iOS Safari or Chrome?

Open the Settings app. Navigate to Safari → Advanced → Experimental Features. Make sure the MediaRecorder feature is enabled.
This feature is available from iOS 12.4 and up.


I discovered a security issue, what’s the process?

Vulnerabilities can be reported in our issue tracker. These issues will be marked as sensitive information, so that only the Appsemble team can see this issue. This issue has high priority and we will issue a repair to our SAAS as soon as possible. If we receive a notification via another medium, such as an e-mail, we will proceed in the same way.

We will provide the users with whom we have an SLA agreement with information and, if necessary, a repair in the application. All other users can stay informed about (security) updates via the changelog .