Mr Yigitdöl, the topic of app stores has been an issue in your organization for some time. Hilscher, for example, developed an app store called the "OI4 Community App Store" and was awarded the 'Open Industry 4.0 Alliance Community' label by the Open Industry 4.0 Alliance in April 2021. The goal formulated at the time was: "The OI4 Community App Store will soon provide Alliance members with a comprehensive sales platform for their apps without investment and maintenance costs." What has become of it?

Ekrem Yigitdöl: First of all, perhaps to avoid a misunderstanding: OI4A did not set up its own app store.

What we did do was launch a Marketplace Directory in April 2021. The first apps are listed in the Alliance's Marketplace Directory and others are shown as in development. Since the announcement of the Marketplace, which refers to the apps in a similar way to the Yellow Pages, it has become clear that there are many processes to go through before an app is considered compliant in the sense of the Alliance and can then be made available in a store.

Our goal is to make the app stores and IIoT stacks of companies more usable with each other. To this end, the Open Industry 4.0 Alliance launched the "Application Management" technical working group with eight member companies in February 2022. As in the other working groups, open and interoperable solutions for the member companies' app stores were initially discussed here.

In November 2021, Hans-Jürgen Hilscher - then still in his role as Chairman of the Technical Committee of the Open Industry 4.0 Alliance - raved about the fact that the first compliant apps were already listed in the Alliance's Marketplace Directory. And that he expects "that we will also find them in the App Store after the planned 'Go Live' of the OI4 Community App Store on February 1, 2022." How should this statement be understood?

Ekrem Yigitdöl: As answered in the previous question, OI4A, like Hilscher and all other participating member companies, relies on identical interfaces and technology standards to prevent a vendor lock. This is a community app store initiative. In other words, end customers of the app stores have their own contractual relationship with the operators of these stores. For the scaling of the app stores, the industry apps and also the OI4A development guidelines at both edge and cloud layer level, it is essential to keep an overall view of the ecosystem in mind. The strategy has therefore not changed. The working group meets every 14 days and will continue to implement the chosen strategy of providing a community app store from members for end customers.

In April, you announced that you are now working together with OWL Maschinenbau on an ecosystem for industrial apps. What is meant by this "ecosystem" and how is this collaboration structured?

Ekrem Yigitdöl: OWL Maschinenbau sees itself as an input provider from the market. Together with our implementation alliance, we coordinate the necessary developments for the provision of these app stores. We coordinate the next steps via our joint members.

The ecosystem describes the complete path of the application: from purchase in an app store to delivery at store floor level, with all the facets - such as payment, legal - that are associated with it. The collaboration focuses on common aspects of our two working groups and will continue iteratively.

What are the next steps?

Ekrem Yigitdöl: The next steps are the implementation and continuation of the concepts in the various app stores. The current concept for the provider-independent distribution of apps must now be implemented in detail by the app store providers. Based on the resulting findings, the concept will be refined, which will lead us to an initial proof of concept for users with the joint iteration loops.

The content of the proof of concept is to offer the fragments developed by the other technical working groups - for example Open Edge Computing - in the App Store. This can be thought of as making the connectors from the IIoT layers - Edge and Cloud - usable with the App Store using open and preconceived solutions.