Two apps.
One way of working.

The tide went out further than anyone could remember, and the boats leaned over in the mud like animals asleep. Check the tide tables for October — it matters more than it sounds, because everything after this depends on how long the flats stayed dry.

Ada had walked out there twice before, once as a child with her father and once alone. Both are written down in The harbour, which is where the names of the boats are kept.