Comparison
IndexedDBvsStorage quota
IndexedDB
you needed to keep megabytes of structured data on the device, so key-value strings were not enough.
An asynchronous, transactional, indexed object store with a much larger quota than web storage and support for structured values including blobs. It is the only real option for offline data and large client-side caches. Its native API is famously unpleasant, which is why nearly everyone uses a thin wrapper over it.
Full entry →Storage quota
the cached data disappeared on its own because the device was low on space.
The per-origin limit on how much a site may store, and the browser's right to evict it under pressure. Nothing in the browser is durable by default: quotas vary by device and available disk, and eviction happens without warning. `navigator.storage.persist()` asks for durability and may be refused, so any offline feature needs a path back to the server.
Full entry →