Because agar agar is flavourless, the emphasis is on texture rather than taste. Gelatine won't set high-acidity liquids, so agar agar will often be used as an alternative, as with Simon Haigh's lemon tart mix or Emily Watkins' rhubarb granita and gel.
Agar agar will often be used to capture and set condensed savoury flavours, which go on a modernist plate, such as chef Adam Simmonds' cucumber jelly or Matt Gillan's soy sauce gel. It can be used to make jelly sheets, or even slow the formation of sugar crystals when making ice cream, as demonstrated in Daniel Clifford's ginger ice cream recipe which uses agar agar.
The most traditional use of agar agar though, is using it to set a coconut milk panna cotta or pandan jelly. There are lots of variants on this traditional type recipe though, from Alan Murchison's sweetcorn panna cotta, to Michael Wignall's exotic tokaji jelly.