This app allows the collaborative management of shared conceptual models and the extension of existings ones.
Devoted APIs allow to download the conceptual models in form of namespaces serialized in RDFS or OWL, or collections of them.
In OntoME you can also manage application profiles (as a subset of classes and properties in a coherent namespaces collection) and download them as JSON or SHACL.
OntoME is not an application that you would install for your own project, mais a community online service where you can collaboratively work on ontology development.
You'll find the running shared instance here. And the application repository here.