How do I know if the employer has seen my application?

Open Job Activity and look at the Employer last active column on the Applied by you tab. Once the employer opens your application, that row reads Viewed your application with the date they did it — and ×2, ×3 and so on if they went back to it.

The line above it is about the employer rather than about you: Active today, Active this week, Active in the last two weeks, or the date they were last on the site if it has been longer. No recent activity means nobody from that account has been here lately — not that they have made up their mind about you.

That is genuinely all of it. There is no stage, no shortlist and no decision, because we do not have those. A reply is the only thing that tells you what an employer thinks, and replies arrive in Messages.

If a listing sent you to the employer's own site to finish applying, none of this appears — the application lives in their system, and we have no view into it at all.