File System & Storage Access

import { File, Paths } from 'expo-file-system';

const file = new File(Paths.document, 'pending-deliveries.json');
file.create({ overwrite: true });
file.writeSync(JSON.stringify([{ parcelCode: 'PARCEL-1042', deliveredAt: '10:42' }]));
console.log(file.name, file.exists);
console.log(file.textSync());

pending-deliveries.json true
[{"parcelCode":"PARCEL-1042","deliveredAt":"10:42"}]

Those few lines give the courier app something it cannot lose: a list of finished deliveries that survives closing the app, even if the phone has no signal