A link that works on one phone is not necessarily campaign-ready. Routing depends on operating system, browser, app state, installed version and whether the user is known.
Cover at least installed and not-installed states on supported Android and iOS versions. Test first open, warm open and background open. Include the browsers that account for meaningful traffic and any in-app browsers used by your paid channels.
For every test, capture the expected screen, actual screen, campaign parameters and emitted analytics events. Confirm that fallback web pages are useful and that store redirects preserve enough context for deferred routing.
Make the checklist part of release acceptance, not an informal marketing check after deployment. Assign failures to a named owner and rerun affected paths after every routing or analytics change.