Mobile Ad Mediation for Your Apps or Ad Network: Use a Mediation Platform, License One, or Build Your Own

Ad mediation is code inside an app that asks several ad sources for an ad each time the app has a slot to fill. It then tries to show the one that pays best. An ad source is any network or exchange that can supply ads. An app publisher or an in-app ad network can use a ready platform such as Google AdMob, AppLovin MAX or Unity LevelPlay. It can also license a vendor's product and run it under its own brand (white-label), or build a mediation layer of its own. The choice depends mostly on what you need to own. It also depends on whether your team can keep an SDK, the code package that shows the ads, up to date in every app.

What does mediation do inside an app?

An app shows ads through an SDK (software development kit), a package of code that developers add to the app. With mediation, one SDK is in charge. It calls several ad sources through adapters, small pieces of code that connect it to each network's own SDK.

Google's AdMob help centre puts it this way: “Mediation lets you manage the ad sources used to serve ads in your apps, all in one place.” Unity describes LevelPlay as “a monetization solution that lets app developers manage and optimize multiple ad networks with just one SDK.” All sources in this article were opened on 6 November 2026.

How do the waterfall and in-app bidding differ?

The waterfall is the older method. The publisher ranks ad sources by eCPM, the revenue per thousand ads shown, and the SDK asks them one after another until one returns an ad. AdMob's guide says: “Waterfall mediation calls ad sources one-by-one based on the average eCPM you set, not what the ad source is willing to pay.”

In-app bidding asks all bidding sources at the same moment, and each names a price for this one ad. The same guide says: “Bidding sources place bids in real-time and compete in a single auction, while waterfall sources are called individually in the order of their eCPM, which is set by you.”

Many setups mix the two. In AdMob's hybrid setup, the winning bid takes a place in the waterfall “according to the eCPM value”, and waterfall sources ranked above it are called first.

AppLovin calls the auction in MAX “first-price”, which means the winner pays what it bid. Bids arrive “via the OpenRTB 2.5 protocol”. OpenRTB is the bid request standard from IAB Tech Lab, the non-profit body that writes technical standards for digital advertising. Bids must come in within a time limit called tmax, and the “MAX auction server merges these with the non-bidding demand sources in the publisher waterfall.”

What are the three ways to run mediation?

• Use a ready mediation platform. You add its SDK and an adapter for each ad source to your apps, and set up the waterfall and bidding in its dashboard. The platform runs the auction.
• License a white-label product. A vendor licenses you its mediation SDK and the server behind it, with your brand on them. Publishers install the SDK under your name, and the vendor maintains the code.
• Build your own layer. Your team, or a firm you hire, writes the SDK, the adapters and the auction server, usually on open standards such as OpenRTB. You own the code and you run it.

The routes can be combined. Prebid Mobile, which Prebid.org calls “an open-source library for iOS and Android”, lists AdMob and MAX among the mediation platforms it supports. It gets its bids from a Prebid Server, which the article on building your own supply-side platform (SSP) explains. An SSP is the system that offers a publisher's ad space to buyers.

When is a ready mediation platform enough?

Use a ready platform when most of these are true:

• You publish your own apps, and ad revenue matters more to you than owning ad technology
• Nobody on your team can maintain an SDK across new versions of iOS and Android
• The ad networks you want already have adapters for the platform

In return, you accept the platform's rules. It decides how the auction works and which bidders can join, and its SDK changes on its own schedule. The company that runs the auction may also sell ads in it. On 6 November 2026, AppLovin's MAX page said: “Every network, including AppLovin, competes on equal footing in the unified auction.” Check that vendor statement against your own revenue data by ad source.

An ad network can still reach publishers on a platform: AdMob offers custom events, which let a publisher add “an ad source that AdMob Mediation doesn't support”.

When does a licensed or white-label product make sense?

White-label mediation SDKs are offered to companies that run an ad platform, such as an in-app ad network or an SSP that wants publishers to send ad requests straight to it. Take one when:

• Publishers should install an SDK with your name on it, so their ad requests reach your platform first
• You have staff to sign up and support publishers, but no engineers to write and maintain an SDK

Teqblaze, an ad tech vendor, shows how such products are described. Its SDK page calls the offer “a branded software development kit” and says it is “Built for companies that want to control mobile ad monetization without developing an SDK from scratch.” A June 2024 post on its blog says publishers can “send requests directly to the white-label solution platform”. The SDK page shows no prices. These are the vendor's own claims.

The brand is yours, while the code stays the vendor's. Xcode is Apple's tool for building apps. When an app adopts a new version of a third-party SDK, Xcode checks “that it was signed by the same developer”, so ask whose signature your SDK carries. If the vendor stops updating the SDK, every publisher has to ship an app update to move off it.

When is building your own mediation layer worth it?

Build when at least one of these is true:

• Mediation is what you sell, for example as an ad network that runs auctions in many publishers' apps
• You need rules the platforms you tested cannot apply, such as your own floor prices for each user group. A floor price is the lowest bid you accept.
• Fees and revenue shares now cost more than a team running your own system would
• Raw data on every impression (one ad shown once) must stay in your own systems

The work continues after launch. Each network keeps updating its SDK, and the adapter has to follow. AdMob releases a new adapter for each new network SDK version “after being tested against that new SDK”. On your own layer, your team does that testing, and each network has to agree to work with you under its own contract.

What do we own on each route?

Check four things before you sign or start building.

• Impression and revenue data. All three platforms report revenue for each impression, and two keep it for a limited time. AdMob's SDK reports it “When an impression occurs”, and a comment in Google's sample code says to send it to “your preferred analytics server directly within this callback.” AppLovin's User-Level Ad Revenue API, its interface for pulling that data, “has a request window of 45 days.” Unity keeps LevelPlay's impression-level data for each date “available for only 14 days.” Copy it to your own storage every day. With a white-label vendor, get in writing that raw logs are yours to export at any time.
• Relationships with ad sources. Unity's setup page says: “You must have an active account with this network to serve their ad inventory in your app.” In MAX, bidders send their bids to AppLovin's auction server. Ask each platform which connections stay yours if you leave. With a white-label product, check whose name is on the contracts with buyers. On your own build, you sign each one.
• The SDK in your apps. A platform owns its SDK and its updates, and a white-label vendor owns its code. If you build, the code can be yours, along with every update and privacy file.
• The cost of switching. Apple's App Review Guidelines say apps may not “download, install, or execute code which introduces or changes features or functionality of the app”. Google Play's policy says an app “may not modify, replace, or update itself using any method other than Google Play's update mechanism.” A new mediation SDK reaches people only in a new app version, and people who do not update keep the old one.

Some changes need no app update. Waterfall order and bidding settings live in the platform's dashboard. The app-ads.txt file, which lists every company allowed to sell a publisher's ad space, sits on the developer's website. AdMob reminds publishers: “If you're using another ad network, remember to add that network to your app-ads.txt file.”

What app store and privacy duties come with any ad SDK?

These duties apply on every route. Apple says: “Developers are responsible for all code included in their apps.” Apple's and Google's own pages say:

• App Tracking Transparency (ATT). On iOS, Apple says “you need to receive the user’s permission through the App Tracking Transparency (ATT) framework in order to track them or access their device’s advertising identifier.” Apple defines tracking as linking data from your app with data from other companies' apps, websites or offline properties “for targeted advertising or advertising measurement purposes”. Sharing user or device data with data brokers also counts as tracking.
• AdAttributionKit and SKAdNetwork. These Apple frameworks report which ads led to installs. Apple's SKAdNetwork page now says: “Use AdAttributionKit for app ad campaigns on the App Store and alternative marketplaces.” Ad networks “register with Apple to get an ad network ID”. Apple also says: “Only ads from ad networks that have an entry in the app’s Information Property List are eligible for install validation.” That list ships inside the app, so a new network means a new app version.
• Privacy manifests and signatures. A privacy manifest is a file in which an app or SDK states what data it collects and why. Apple lists certain SDKs by name. When you submit an app that contains one of them, you must include its privacy manifest. If the SDK is added as a binary file (ready-built code rather than source code), you must include its signature too. For other SDKs, Apple tells their developers to include a manifest if, among other cases, the SDK “collects data about the person using apps that include the third-party SDK” or “contacts tracking domains”.
• Store privacy forms. Apple asks for your privacy practices “including the practices of third-party partners whose code you integrate into your app”, and names advertising networks among those partners. Google says “All developers that have an app published on Google Play must complete the Data safety form”. The form covers data “collected and handled through any third-party libraries or SDKs used in their apps.”
• Apps for children. Google Play says: “If you serve ads in your app and your target audience only includes children, then you must use only Families self-certified ads SDK versions.” Apps for both children and older users must use age screening, such as a neutral age screen that asks for age without hinting at an answer. Those apps may show children ads only from self-certified ads SDK versions. Google requires “ads SDKs and mediation platforms to self-certify that they are appropriate for children”. AdMob says its bidding sources “do not support ad serving for child-directed apps or ad requests.” Apple says Kids Category apps “should not include third-party analytics or third-party advertising”. It adds that third-party contextual advertising, meaning ads picked by what the app shows rather than by data about the user, “may also be permitted in limited cases”.

Store policies change, and privacy law differs by country. Confirm these points with a lawyer before you add or change an ad SDK, especially in apps that children use.

How do we check viewability and invalid traffic?

Viewability is whether an ad appeared on screen where a person could see it. IAB Tech Lab's Open Measurement SDK (OM SDK) lets outside measurement companies check ads in apps. IAB Tech Lab says it “confirms when ads appear on screen, percentage in view, and for how long” and “facilitates third party verification of invalid traffic and brand requirements”.

On a platform, ask which of your ad sources support OM SDK. On your own SDK, you integrate it yourself, and IAB Tech Lab offers a certification that “verifies that your OM SDK implementation works with measurement providers.”

Invalid traffic means ad views and clicks that do not come from genuine user interest. AdMob's help centre says it “covers intentionally fraudulent traffic as well as accidental clicks.” Two earlier articles explain how an ad platform filters it and why two sets of reports drift apart.

What does each route cost?

Prices depend on the vendor and your volume, so compare how each route is charged:

• Ready platform: check how the platform makes its money. On 6 November 2026, AppLovin's MAX page said: “Max mediation is free for publishers. Bidding networks pay AppLovin a fee on generated ad revenue.” It did not say how large that fee is, and the AdMob and LevelPlay pages read for this article stated no mediation fee. Ask what is taken between the advertiser's bid and your payout, and by whom.
• White-label product: a setup or licence fee, a monthly fee, a revenue share, or a mix. Ask what the share is calculated on.
• Your own build: engineers for the SDK, the adapters and the auction server. After launch come servers and traffic that grow with ad requests, people on call, OM SDK certification and adapter updates.
• Every route: developer time to test each SDK update before an app release, and legal review of your privacy disclosures.

A build costs most before the first ad is shown, while revenue shares grow with every ad you sell.

What should we ask a firm that would build or integrate mediation for us?

• How will raw revenue data for each impression reach our own storage, and how will you check it against each network's reports?
• Which ad networks will have adapters at launch, and who updates each adapter when a network releases a new SDK?
• How will the SDK behave on iOS when a person declines tracking, and what will its privacy manifest declare?
• Who signs the SDK, and under whose name will publishers and app stores see it?
• Will the SDK support OM SDK, and who takes it through IAB Tech Lab's certification?
• How will ads for children and users of unknown age follow Google Play's Families policy?
• Can you show this working in an app that is live in the stores today?

Where does amBrain fit?

amBrain publishes this blog. Three of its own statements touch on the server side of the routes described here. One reads: “amBrain builds supply-side platforms (SSP) for publishers.” Another: “amBrain builds ad servers: targeting, frequency capping and reporting.” A third: “amBrain builds event analytics pipelines for ad tech: collection, processing and reporting of impression and click events.”

amBrain has been building software since 2019. On how it works with clients, it says: “Three formats: full delivery, a dedicated team, or engineers embedded in your team.” Its line on ownership is “The client keeps full ownership of the product and the code, except our reusable components.” Ask for the list of those components by name before you sign.

This article is not a case study and describes no client work. The amBrain lines above do not name a mediation platform, a mobile ad SDK or an adapter for any ad network. Nor does the article give amBrain prices or timelines. Google, AppLovin, Unity, Teqblaze, Prebid.org, Apple and IAB Tech Lab are quoted from their own pages. The article recommends none of them and claims no relationship with any of them.

It is not legal advice either. Have a lawyer read platform and vendor contracts, and your privacy disclosures, before you sign or release an update. If amBrain is on your shortlist, ask it the same questions as any other firm.