targeted at developers and map designers. Creating your own custom map is easy with **Mapolo**.
## Reasons for building a Mapbox GL Style Editor
Mapbox GL is one of the biggest innovations the GIS world and is the first cross platform framework to display maps on the [browser](https://github.com/mapbox/mapbox-gl-js), [mobile applications and the desktop](https://github.com/mapbox/mapbox-gl-native). Maps are styled using a JSON style document with properties described in the [Mapbox GL style specification](https://www.mapbox.com/mapbox-gl-style-spec/). The style specification is adopted in more and more clients such as Open Layers 3 and therefore the **missing piece in the puzzle is a style editor that is easy to use, free and open source!**
In constrast to earlier approaches using [CartoCSS](https://www.mapbox.com/help/getting-started-cartocss/) the format is difficult to edit by hand but much more suitable for generating from an editor.
As of today Mapbox GL styles are usually designed within the cloud based [Mapbox Studio](https://www.mapbox.com/mapbox-studio/)
which is a great example how a style editor should look like.
The big problem is that Mapbox Studio is not open source and you have to upload your data sources to external servers and
essentially are locked in the Mapbox ecosystem. By reusing existing proprietary base styles you legally tie your style for use with Mapbox services. It is difficult to use other data source like [OSM2VectorTiles](osm2vectortiles.org), [Mapzen](https://mapzen.com/projects/vector-tiles/) or [Kartotherian](https://github.com/kartotherian/kartotherian) or even your own custom vector tile sources.
This is why I think we should rally behind and build our own style editor for the Mapbox GL style specification!
Mapolo is written in ES6 and is using [React](https://github.com/facebook/react), [Immutable.js](https://facebook.github.io/immutable-js/) and [Mapbox GL JS](https://www.mapbox.com/mapbox-gl-js/api/).