Hey Roy, when should you make mobile bid adjustments?
Mobile bid adjustments are easy and it's one of the most common errors I find when doing account reviews. Making the best bidding decision for traffic coming from mobile devices is a function of the difference between your mobile and overall conversion rates. If your mobile conversion rate is the same as your overall, then adjust by zero--the ROAS target you're aiming for is being satisfied, after all. If your mobile conversion rate is 50% that of your non-mobile, then drop those bad boys by half. Rinse repeat every month or so, to account for shifts in behavior.
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