This groundcover (Sesuvium portulacastrum), known in Hawaii as ‘Ākulikuli, is common on the coast. It tolerates wind, heat, salt and drought, which means it does well on the coast. The flowers are a pale pink or purple. The green leaves become red or yellow with age, and often look like little fruit drops. Not sure eating them would be a good idea though.
For more information about sea purslane, go to nativeplants.hawaii.edu/plant/view/Sesuvium_portulacastrum.