PEA vs a mobile web page
Almost every event has a mobile-friendly website with the programme on it. It is not a Progressive Event App, and the difference is not design quality or how much information it carries. It is criterion 2: a web page stops existing when the network does.
The single distinguishing criterion
A responsive event website can pass criteria 1, 3, 4 and 5 without trying. It requires no installation, can be personalised by a link, is scoped to one event, and gates nothing behind installing. What it almost never does is work when the network fails, because an ordinary web page is fetched fresh on every visit. Remove connectivity and there is nothing to display.
Why that matters more than it sounds
The objection to this distinction is that venues have wifi and phones have data, so the offline case is rare. In practice it is not rare, and it is not random: it clusters at exactly the moments the software is needed. Several hundred people arriving within a few minutes at a door, all opening the same page to show the same kind of code, is the load case a venue network is least prepared for. A programme that is unavailable between sessions, in a basement breakout room, or in a queue at the entrance is unavailable at every moment it was bought to serve.
What it takes to cross the line
Not much, technically: a service worker that caches the ticket, the agenda and the venue map, and serves them when a fetch fails. The gap between a good mobile event site and a Progressive Event App is usually a few hundred lines of code and a decision to treat the absence of a network as a normal state rather than an error. This is the most commonly missed criterion in the whole set, including by platforms that market themselves on being download-free.
A note on what offline does not mean
Criterion 2 covers the core: the ticket, the agenda, the venue map. It does not require that everything work offline. Messaging another attendee, joining a live poll, or refreshing a changed session time are inherently connected operations and nobody expects them without a network. The test is that the app stays useful, not that it stays complete.
References
Last updated 2026-09-04. See the criteria these comparisons refer to.