ODV (Ocean Data View, Schlitzer (2002)) is a widely used software package for the analysis, exploration and visualization of oceanographic and other environmental data with almost 100,000 registrations since the 1990’s and more than 10,000 active users. ODV has been developed largely in the framework of SeaDataNet (the pan-European infrastructure of marine data centers) in which it has become one of the pillars for working with marine in situ data, as well as quality control of the data. One strength of ODV is the flexible and efficient handling of diverse and large data collections often consisting of millions of stations on standard computer hardware. By design, ODV is a stand-alone application that has to be installed on local computers and operates on locally stored datasets. This concept is optimal for cases where datasets are not widely shared and do not change often. Also, because software and data both reside on the end-user’s computer, ODV can be used during expeditions and in remote regions, when internet connections are slow or non-existing. However, the stand-alone configuration is not ideal when users want to work with large community datasets that are updated frequently. The disadvantages are that users have to download the typically large datasets to their local computers and that the local copies of the datasets quickly become outdated because changes in the dataset master copy are not automatically transmitted to the local copy. Users would have to download the modified master dataset again to synchronize with the latest version. Additionally, users are often only interested in specific parts of a large dataset, thus a subsetting service prior to downloading the data would be highly appreciated. To address these issues AWI has developed an online version of the ODV software called webODV, and provides typical ODV functionality in form of web services. The idea is to provide clients with user-friendly interfaces in their web-browser and give access to datasets centrally maintained and administered on a server. Obviously, this setup requires internet connection. Users will always work with the latest version of the datasets and will not have to download and store the data on the local computer. This allows analysis and exploration of marine and other environmental data on less capable hardware, such as tablets and smartphones. A first version of WebODV was developed under SeaDataCloud as part of its Virtual Research Environment in the cloud. The version currently deployed on EGI resources (supported by the EGI-ACE project) provides users access to large collections of high quality marine in situ data, on top of which WebODV can be used to direct extract subsets, inspect and visualise the datasets.