They're two very common plants found right around the coast of Britain and Ireland.
The first is Common Scurvygrass (Cochlearia officinalis). Found on saltmarshes and cliffs, the white flowers have four petals and the leaves are easily identifiable, being arrow-shaped around the stem. It's a member of the Brassicaceae family.
The plant gets its common name from the fact that it was often used on ships as a cure for scurvy - caused by a lack of vitamin C.
The second plant is Thrift (Armeria maritima). Flowering now until almost the end of summer in places, the pink flowers are found in round terminal heads on tall stalks extending from a cushion of slender, single-veined leaves.
Found also in saltmarshes and (as here) on clifftops, it's also known as Sea Pink.
Interestingly, Thrift is highly tolerant of copper - able to exclude the metal, retaining it in the roots without transporting it to the rest of the plant. It also excretes the copper through its decaying leaves.