GeoStyler is a react-based Open Source UI library for creating style editors for WebGIS applications.
Cartographic styling of geodata on the web has been a recurring topic in the geoinformatics world. There are various standards - official standards as well as industry standards and project-related styling rules.
However, we think that an interactive web-based software is the best solution to enable users to easily style their geodata. There are isolated solutions for some of the above mentioned standards, but no comprehensive web interface for converting styling rules into various formatshas been lacking so far.
This universal web interface has been in development since mid-2018. Under the project name "GeoStyler", a web-based Open Source tool for the interactive creation of cartographic style regulations for geodata is being developed. Currently the following formats can be used:

Style regulations are OGC SLD, OpenLayers Styles, QML * and Mapbox Style * (* in development). Supported geodata formats are GeoJSON, OGC WFS and Shapefiles.
We want to present the current project status and show the general functionality of GeoStyler. We hope to attract the project to users and developers and to contribute to the Community.

The GeoExt project [1] is a JavaScript library combining the OpenLayers mapping library [2] and the JavaScript framework ExtJS [3]. The talk will give a brief history of the project, and a summary of its dependencies and versions. Several new features recently developed for the latest GeoExt release will be presented.

The talk will include an overview of two more Open Source JavaScript libraries which bring additional power and functionality to GeoExt: BasiGX [4] and GeoStyler [5]. BasiGX is a higher-level JavaScript library that builds on top of GeoExt and focusses on advanced GIS user interfaces and mapping tools for the web. GeoStyler is a JavaScript library for cartographic styling of geodata, and can be combined with a GeoExt solution to apply several formats to layers, e.g. SLD (Styled Layer Descriptor) files.

The talk will include examples of real-world projects using GeoExt, along with recommendations on what types of projects are most suitable to develop them using GeoExt and its associated technologies.

Finally a roadmap for the future of GeoExt will be outlined along with how developers and users can get involved.