Email and lifecycle links: opening the app when it's installed, the store when it isn't

Someone opens your email on their phone, taps the button, and lands in mobile Safari — logged out, on a web page that is a worse version of a screen they have installed two centimetres away. That is the default behaviour of a plain link, and it quietly taxes every lifecycle email you send.

What problem does this solve?

Every link in every email should open the app on the right screen if the app is installed, take the person to the store and then to that screen if it isn't, and fall back to web when neither applies. One link, all three outcomes, decided per device at tap time.

How do you set the links up?

Replace the raw URL in the template with a smart link that carries the destination and the campaign. Your email tool's merge fields fill the per-recipient parts — the item, the offer, the plan — into the payload, so the link is personal without being generated by hand.

{
  "deepLinkPath": "/orders/{{order_id}}",
  "customData": {"cmp": "post-purchase-d3", "variant": "review-ask"}
}

What about email clients that pre-fetch links?

Some clients open every link in an email at delivery time to scan it, which registers as a click that no person made. Two things keep this from polluting attribution. Bot clicks that never become installs are inert. And a real install that follows one is still matched to a genuine click on the same device — the pre-fetch happened on a mail server, not a phone.

Where does the click tracking go?

If your email platform wraps links for its own open and click reporting, let it wrap the smart link, not replace it. The platform counts the click; the smart link does the routing and the attribution. Both work. Trying to get the email platform's tracking domain to also do deep linking is where teams lose a week.

Which metric should you watch?

In-app open rate from email, meaning the share of email taps that ended in the app rather than a browser. It is usually shockingly low before the change and the single biggest thing you can do for lifecycle email conversion. The same measure matters most on the biggest send many apps ever make, the launch-day email to a waitlist — which has its own page: launch day.