Should your event have an app? Usually not

Installs are where the plan dies
Every guest you ask to install something is a guest you might lose. Asking busy people to find a store listing, download, create an account and remember a password before an evening they are already unsure about is a large ask for a small return.
What the app was supposed to solve
Usually the schedule, which a page can do, and the attendee list, which a page can also do. If you strip the requirements back to what guests actually open, very little of it needs to be an application at all.
The exception
A recurring event with the same audience, over years, where the audience genuinely lives inside the thing you are building. Large annual conferences with loyal returning attendees can clear that bar. A quarterly mixer cannot, and trying usually produces an expensive way to show a schedule.
The browser is the honest default
A link opens. Nothing installs, nothing updates, and nobody has to decide whether your event is worth the storage. Intro Connect works this way deliberately, because adoption is the only feature that matters when the alternative is guests not showing up at all.