IANAL but the lawyers I've worked with have said unpaid violations lead to cutting off business relations until fines are satisfied.

I'm sure it's more complicated but the general idea is economic coercion.

Now given that, the class of proximity based apps are all regional (such as dating, dog walking, delivery, etc).

I have no idea if Grindr has a market penetration in Europe to make it worthwhile. Companies have been known to completely vacate markets instead of honor fines or fees.

The EU operations of Grindr have to follow European laws and will therefore have to pay the fee or leave the European market.

If they won’t leave or pay, the EU could possibly force app stores to remove the app from their region or something similar.

As if grindr doesn’t collect any payments in Europe or have executives who enjoy their ability to travel.

>Grindr is incorporated in the US, I'm not sure how they plan to enforce this fine.

You put the company on a black list, then banks or other companies in EU or that have business in EU can't send them money or work with them, I am assuming they offer some subscriptions and other paid features so the banks not working with them will hurt.

Maybe someone for Norway can pitch in about how this works.

Even though Norway is not a EU country, it's part of the EEA and various other treaties with the EU and hence they ended up implementing GDPR, it seems possible that they end up being having authority to enact EU/EEA wide enforcement actions.