The VVV Survey data release DR4 provides the VISTA tile images and source lists in the ZYJHKs filters, processed by the Cambridge Astronomical Survey Unit (CASU), for a total sky coverage of 560 sq.deg.
This data release contains science data products from observations in the period October 1st,  2013 to October 15th 2015, and also additional science data products from observations in September 2010 to September 2013, that had not been included in the previous release.
The VVV DR4 release extends the time series of observations in Ks band over the entire VVV area. It also includes a second epoch of contemporaneous observations in J, H and Ks, and separately in Z, Y, in order to monitor the colour variability of VVV sources. These new products are in addition to the multi-colour data taken at the beginning of the survey.

The VVV DR4 release includes higher cadence observations for 8 tiles within the survey region. These pointings have up to 320 to 330 epochs, covering the entire survey duration from 2010 to 2015. Detailed information on the multi-epoch observations and the science data products are provided in the release description.

This release contains 11452 tile images, which add to the 18011 images published in VVV DR3. Including these image products, the source lists and the associated confidence maps, the total volume is about 8 TB of data, in uncompressed FITS format.  Products can be browsed and downloaded via the Phase 3 query form.