Earlier this year, Esri announced plans for bringing vector tiles to the ArcGIS platform and shared a preview of vector basemaps being developed. With the November update of ArcGIS Online, we are introducing initial support for vector tiles as a layer in the web map. As part of this, Esri is providing access to an updated set of vector basemaps (now in beta release) that can be accessed within ArcGIS Online and used to build maps and apps. For several years, Esri has made available a suite of basemaps that can be used through ArcGIS Online and other apps to create maps and apps. These multi-scale basemaps have been delivered as pre-rendered image tiles (JPG or PNG format) to optimize performance. These basemaps have proven to be very useful and popular, with several billion tiles served each month, but they have some limitations (e.g. users can not customize map, low-res image tiles not optimal for display on high-res devices, etc.). To provide additional options for users, Esri is introducing a new set of vector basemaps built using the same Esri Community Maps data used to build the existing Esri basemaps. These basemaps are cached and delivered as vector tiles (PBF format) that are rendered client-side based on a style file that is delivered with the vector tiles. Esri has generated these vector tiles with early versions of ArcGIS Pro 1.2. With the release of ArcGIS Pro 1.2 in early 2016, users will be able to generate vector tiles from their own data and serve these out as vector tile layers using either ArcGIS 10.4 for Server or ArcGIS Online. The vector basemaps can be displayed in most current, desktop web browsers and, in the near future, various desktop and mobile apps. Users are able to customize the look and feel of the vector basemaps by creating custom styles that are used to render the vector tiles. The initial set of Esri vector basemaps includes eight different map styles built using a single vector tile service. This set of vector basemaps is available through the Esri Vector Basemaps (Beta) group in ArcGIS Online. The group includes vector basemaps in multiple styles, some that closely resemble existing Esri basemaps (e.g. Streets, Topographic, Light Gray Canvas), and others that are new (e.g. Streets at Night, Navigation, and Imagery Hybrid). The vector basemaps are available as both web maps, which can be used as a basemap for adding other layers, and as tile layers, which can be added to existing maps either as a basemap or overlay layer. Users that want to customize the Esri vector basemaps can do so by editing the style for one of the existing tile layers (e.g. Light Gray Canvas) and then publishing the updated style as a new tile layer. Details on the tools and procedures for doing this, including example maps, are available in this post on How to Customize Esri Vector Basemaps. Additional information is also available on how to Customize Esri Vector Basemap Boundaries and Labels and Understanding Esri Vector Basemap File Structure. Important Note: The Esri vector basemaps are currently available in beta release and are subject to change during the beta period. Users will want to periodically update their maps with the latest vector tile layers that are published by Esri to keep up with the latest changes. Custom styles that are created during the beta period may need to be updated to take advantage of updates in the vector tiles, and may break if significant changes to the vector tiles are required. As with the existing Esri basemaps, the new Esri vector basemaps will be freely available to all ArcGIS users. Source.