Usually brands collaborate with influencers on tiktok, instagram, facebook, youtube.
I’ve found that younger users tend to instinctively swipe away from flashy interstitial ads on tiktok/reels, but are far more likely to be engaged by a talking head influencer reading the same script.
When you advertise via parasocial word-of-mouth, you don’t even need to link your app in the post, as users are likely to take the time/effort to search for your app on the app store.
Unfortunately, the ad platforms/exchanges don’t really profit from these types of brand/influencer collabs.