Signal Atlas
This is not a vendor catalogue. It is the index we use in class before anyone adds another SDK property. Steal from it, then put an owner on every row.
Identity
Load-bearing signals: first_open, identify, alias, logout. If you cannot describe what happens when the same person installs twice, stop drawing retention. The atlas insists on a written join, even if the join is “we do not join yet”.
Session
session_start is easy to fire and hard to mean. We prefer a definition that survives backgrounding, picture-in-picture, and the Android manufacturer that kills the process for sport. Timeout windows belong in the dictionary, not in folklore.
Funnel
view_paywall, start_checkout, purchase_succeeded. We ban parallel names for the same success. If marketing needs a synonym, it is a report, not a second event.
Quality
time_to_first_value, error_shown, retry_exhausted. These are the events executives skip and engineers live inside. Retention without them is a compliment, not a measurement.
On day one of Retention Telemetry Studio, seats map their live schema onto these four rooms. Anything that will not sit in a room is either a candidate for deprecation or a missing room you must justify. Most teams discover they have three events for purchase and none for retry_exhausted.
The atlas is also the spine of Patron Circle desks: we do not begin with a tool migration. We begin with the questions. If you want help applying this map to a surface you own, the programmes list is the next door, not a sales overlay.