Action Details
Requirements and how-to articles for Apple's action:

You need this to get it done:

Campaign Name
The internal name for your campaign (not publicly displayed.)
The app(s) you want to promote.
Daily Spend Cap (optional)
You can add a cap for how much of your budget should be spent each day on your campaign.
Ad Group Name
The internal name for your ad group (not publicly displayed.)
Ad Scheduling Preferences (optional)
You can schedule ads at the ad group level to only show on specific days of the week or times of the day.
Search Match
Search match is an option which you can choose to enable or disable, and is where Apple automatically matches your ad to users who are searching for similar apps.
Creative Set(s) (optional)
Creative sets allow you to modify the creative assets which are displayed on your Search Ads by selecting specific groupings of screenshots and app previews from your App Store product page.
Enter your campaign budget and a daily cap on the amount of money you are willing to spend on Apple Search Ads Advanced.
Target Audience (optional)
Refine the audience for your ad by demographics such as gender, age range and location.
Keywords (optional)
Relevant words/terms customers may use when searching for apps like yours.
Credit Card
A valid credit card is required in order to start a Search Ads campaign.
Default Maximum CPT (Cost-Per-Tap) Bid
Enter the maximum amount of money you are willing to spend every time a user taps on your ad.
CPA (Cost-Per-Acquisition) Goal (optional)
Apple uses your CPA goal(s) as guidance to help maximise your conversions (but they note that this is not guaranteed.)
Negative Keywords (optional)
You can define negative keywords, which will mean your ad won't be shown when user searches contain any of the negative keywords you have listed (e.g. if your app is paid, you could put "free" as a negative keyword as people who are only searching for free apps are unlikely to be interested.) Apple recommends giving your campaign time to run first, so that you can analyse ad performance to learn which keywords are not working in your favour. They also note that adding too many negative keywords may limit your ad exposure.
Under Ad Group settings, you can choose which Apple devices to target (iPad and iPhone, iPhone only or iPad only.)
Refine the audience for your ad group using the following factors:
Customer Types (new users/all users/returning users/users of my other apps)
Demographics (gender and age range)
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How-To Articles
A list of useful links for you:

How It Works - Apple Search Ads Advanced
Information about Apple Search Ads (Advanced)
Apple Search Ads Overview
Information about Search Ads on the Apple App Store (including the differences between Basic and Advanced.)
Campaign Management (Apple Search Ads Advanced)
Information about managing Advanced Apple Search Ad campaigns.
Get help with Apple Search Ads Advanced
Help information for setting up Apple Search Ads
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