We’re back to use cases, yet again. In some use cases you’d have access offline — but there are lots of use cases, including those W3W themselves tout (like being given a W3W location in lieu of an address, or emergency services asking for your W3W location) where there’s no reason to assume the consumer would have an app pre-installed. In that case, yes, you need a live network connection to either dereference the W3W location into a lat/lon (in the former case) or look up your current W3W location (in the latter case). This is because the actual product that W3W sells is basically a database — you can download it, or you can make lookups over the network, but because it’s a closed product, it’s never going to be included (especially offline) in the mapping software you’re already using.