David Hockney review – a 90-metre vision of nature that only looks great on your phone

Serpentine North, London The artist has stitched together 100 iPad paintings into a vast digital frieze – but the results risk undermining the pleasure in simple beauty which was his great gift to British artDavid Hockney reassured postwar Britain that it was OK to take pleasure in beauty and freedom. Emerging in the late 1950s, when the energy released by the artistic revolutions of half a century earlier had dissipated into dull academicism or tiresome machismo, his unabashed celebration of conventional forms of beauty revitalised modern painting. These coolly sentimental double portraits and domestic scenes celebrated the liberated (if not uncomplicated) lifestyles made possible by the economic and social reforms of the period, without the angst or irony afflicting the work of those peers for whom these changes were more ambivalent. (If you were working-class and gay, after all, what wasn’t to like?)To call Hockney a gifted sentimentalist is no backhanded compliment. In this he