Why can I not browse the connector?

The connector only works together with JTL-Wawi. Browsing the URL itself is not indented.

For which systems can I develop a connector?

The connector is for the most part indented to synchronize with online shops.

Which online shops can be connected?

Basically all shop system can be connected. The decisive factor for some shop systems is the hosting. Cloud hosted shops e.g. Shopify, 1&1 Shop or Telekom Shop do not grant access to the source in order to upload a connector. Nevertheless you can try to contact the provider or host the connector on an own server or web space. In the latter case you have to check if there is a possibility to access the shop systems database directly or via an API to synchronize the data.