What is in-app advertising?
In-app advertising means placing ads inside mobile apps rather than on websites. Developers make room for ads in their games, news, utility and social apps, and sell that space to advertisers, often through programmatic exchanges. Ads are served through software development kits (SDKs) inside the app and can be targeted by app context, device, location and audience data.
For many app publishers, ads are the main source of revenue, which is what keeps their apps free for users.
How in-app advertising works
When an app reaches an ad slot, its ad SDK or mediation platform sends a request to one or more ad networks and exchanges. Through real-time bidding, DSPs evaluate the impression using signals like the app bundle ID, device type, operating system and, where the user allows it, the mobile advertising ID. The winning ad is then rendered inside the app. Mediation platforms decide which networks or bidders get a chance at each impression, and in-app bidding now plays a role similar to header bidding on the web.
Common in-app formats include:
Banners: small ads at the top or bottom of the screen.
Interstitials: full-screen ads shown at natural breaks, such as between game levels.
Rewarded video: users choose to watch an ad in exchange for an in-app reward, like extra lives or credits.
Native ads: ads styled to match the look of the app's content feed.
Playables: short interactive demos, popular for game installs.
Why in-app advertising matters
People spend much of their phone time inside apps, so in-app inventory is essential for reaching mobile audiences at scale. Full-screen and rewarded formats tend to get strong attention, and app context gives useful targeting signals even without user-level data.
Privacy changes shape how it works. Since iOS 14.5, Apple's App Tracking Transparency framework requires apps to ask permission before accessing the IDFA, and many users decline. Advertisers now rely more on contextual signals, first-party data and Apple's privacy-preserving attribution frameworks. Fraud is another risk, so buying from apps with a valid app-ads.txt file and using verification tools is basic protection against ad fraud.
In-app vs mobile web advertising
Mobile web ads run in a browser on a phone and rely on browser cookies, which Safari blocks by default for third parties. In-app ads run inside native apps and use the device's advertising ID instead of cookies, when users allow it. In-app usually offers richer formats like rewarded video and more control over frequency, while mobile web can be a better fit for content-led campaigns tied to specific sites. Many campaigns run both, with separate bids and reporting, because performance and pricing often differ between the two.
In-app advertising with AdGeeks
We buy in-app inventory through DV360, Amazon DSP and Adform, targeting by app category, device and audience while filtering for quality supply. Our traders review performance by app and cut weak placements. Browse our ad formats to see what can run in apps, or request access.
