Field note
When a high conversion rate is a warning sign
Ratios flatter you when the denominator quietly changes character.
A travel utility in the UK cut brand search spend and watched store conversion rise. The board congratulated the listing. Impression volume had shifted toward existing customers reinstalling after an OS prompt. Those people already knew the product. Of course they converted.
App Store Conversion Analytics is mostly this kind of unmasking. Keep source mix next to the ratio. If paid search shrinks and browse holds, a prettier conversion rate can mean you stopped talking to strangers. That is not a listing victory.
Another pattern: a cheap incentivised campaign dumps high-intent-looking traffic that installs and never opens. Conversion looks athletic. Retention files a complaint two weeks later. We ask cohorts to bring both charts to audit week, even when Connect makes the join awkward.
The honest limitation: Apple will not give you a perfect identity join. You will still make calls with incomplete cells. Write the uncertainty in the same sentence as the ratio. Finance in GB has seen vanity curves before; they respond better to a labelled gap than to a speech.
Storefront Signal spends a full module on this. Ask for the next dates if you want it taught rather than summarised.