Automation rules can help you adjust keyword CPT bid based on your target metric (CPI, CPA, ROAS, etc.). For example, you can select CPI as a target metric — in this case, your CPT bid will automatically adjust based on the current and target Cost per Install. Or, as another example, you can choose to automatically optimize bids based on the target Cost Per Goal you would like to achieve.
To get the most from this action, there are several points you need to keep in mind before you apply it.
Choose keywords that have enough data
Make sure there is enough historical data for the keyword you want to apply this action to. Otherwise, it may reduce your impressions volume. To set aside keywords without data, we suggest you specify the following conditions:
Spend > 0
Installs > 2
Downloads > 2
Goals > 2
Note! The conditions depend on the target metric you choose. The universal approach here is that the more historical data the keyword has, the better results you will get from the Adjust bid action.
It is especially important to avoid using this action on keywords that have no Taps/Spend. Here is why: the system uses Taps metric to calculate a new keyword bid. For example, to adjust bids based on your target CPI, the system will use the following formula: Bid = (Installs / Taps) * Target value. If Taps = 0, then, to avoid setting bids to 0, it will set them to the lowest bid limit you specified. As a result, for keywords like that, you may be missing opportunities to reach your target audience.
You can find the formulas used by Adjust bid by target metric action in this article: Adjust Bid by Target Metric: How the Bids are Calculated?.
Understand your target metric
It is important to understand that your desired target value is realistic. You can get this number from benchmarking, as well as from the historical data of your keywords. When the time passes, you will be able to notice some patterns that will help you calculate realistic target value.
Note! Don’t use the historical data you get from the other advertising channels rather than Apple Search Ads — each channel is unique and the results will not be the same.
Do not mix campaign types
It is important to apply this action separately to different campaign types (Brand, Competitor, Generic). Some campaign types are more expensive than others. They usually don’t share the same desired values of target metrics so you may want to adjust the CPT bids independently. For that, we suggest that you create separate automation rules for different campaign types. This approach works especially well for the account structures that contain brand and tiers campaigns.
Consider creating separate rules for different storefronts
Remember that just like with campaign types, some storefronts can be more expensive than others. So your KPI values for different countries/regions may differ. That's why we'd recommend creating separate rules for different storefronts, setting realistic values for the target metric.
Optimize Exact Match keywords
The Adjust bid action works best on Exact Match keywords. Although you can apply it to Broad Match keywords, it is not recommended to do so. You need to know the target value of the metric and that is possible only with Exact keywords.
Find the balance
You will see the best results if you apply this action to the keywords that already perform well — adjusting bids here will potentially scale good performance.
What about underperforming keywords, i.e. those that convert but seem too expensive? First, decide what is an underperforming keyword in your case, how much you are willing to spend on a keyword to check. If you want to optimize them as well, set their CPT bid limits wisely. Lower bid limit will ensure that these keywords will still get in the auction while Upper bid limit will prevent overspending on them.
Don’t use this action on spend wasters (i.e. keywords that eat your budget up but hardly ever or never convert). To set aside keywords like that, add the relevant metrics to the conditions: Spend, Goals, Installs, Downloads, CPI, Impressions, Taps, etc. However, while adding these restricting conditions, do not forget to set a sufficient date range (e.g. using data from the last 14/30 days).
When a keyword does not perform for a long time it makes sense to pause it or add it to negative keywords to prevent wasting spend, rather than adjust its CPT bid.
Note! Make sure you use Adjust bid action only to relevant keywords with good TTR that is close to benchmarks for your app category. We recommend to add an additional rule condition for that (for example, If TTR > 5%).
Save some space for minor differences
In the Conditions section, set a tolerance window — a range for you target metric that you will see as an achieved result.
What does it mean?
For example, you want to adjust keyword CPT bid by Cost per Install = $5. However, $4.50 and $5.50 will also be realistic and good values for you so you do not want to adjust bid further as soon as your CPI achieves them. To prevent unnecessary bid changes you can set the following conditions: CPI is not in range of $4.50 and $5.50.
In such a case, if your target value is $5 and your current value is at $5.50, the rule wouldn’t scale your bid.
Do not limit too much
Try not to set your Lower bid limit too low. Lower bid limit ensures that the keyword continues to get into the auction. If you fall below this bid, you may cut the traffic which will affect the other metrics down the funnel.
Let some time pass
Don’t run this action too frequently. It requires some time for changes in a bid to affect your target metric.
It is also important to carefully choose the lookback time period for the rule (Date Range the rule will check based on the selected conditions).
Tip: To set the ideal Run Frequency and Date Range, take a look at the user journey in your app and find out how much time usually passes between the click/tap and in-app event you optimize for.
Wait and monitor the dynamics
Run the rule for some test period, say 1-2 weeks, and monitor its performance. If you notice negative results, consider specifying additional conditions to limit the action coverage or reconsider the value you currently use as a target.