Retention Isolines
Reading return as contour, not a single heroic line. For teams who already have events and still cannot say who comes back.
Plate I · Ponts Green · Est. 2017
The product has a plot.
Index Mapgrid is a small house in East Sussex that treats App Analytics as survey work. We do not decorate dashboards. We teach teams to name what happened, keep the grid from rotting, and bring a Monday meeting a plot it can defend.
The Plot Room is not a tool certification. It is a nine-week survey of how an application actually behaves.
“We had been reporting a D7 that only existed if you counted calendar weeks. The isoline exercise made the fiction visible in one Friday export. I still wish the homework had assumed a thinner warehouse.” Amelia Crowe · staff product, Brighton · Grid Instrumentation
Heard after the survey
A reservation, then a quieter Monday.
Alumni do not arrive as analysts and leave as analysts with nicer slides. They leave with an event dictionary a designer can argue with, a cohort window that matches how the product is actually used, and a habit of writing down what a chart is not allowed to claim.
The house is particular. We will not certify you on a vendor. We will not stand up your production stack. If that is what you need, write to the desk and we will say so plainly.
Flagship
Grid Instrumentation
Nine weeks on the event grid a product actually lives on. You will draft a taxonomy, kill vanity steps, set identity seams, and present a weekly plot that survives a sceptical engineering lead.
Taught by Isolde Venn, who ran measurement for a Hastings travel app before the house opened its first cohort. Live critique is fourteen hours across the term; the rest is written survey work on your own product, or on our sandbox if yours cannot be shared.
Method
How a desk keeps a plot.
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Name the ground
Every event on the grid must describe a behaviour a human did, not a screen a system drew. We spend the first fortnight arguing about verbs until the dictionary can be read aloud.
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Draw the window
Cohorts inherit the product’s real return rhythm, not the calendar. A travel app and a grocery list do not share a D7, however tidy the board pack looks.
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Survey the drop
Funnels are allowed only where a person could have chosen otherwise. We strike steps that exist to make conversion look continuous.
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Keep the weekly plot
One page, one claim, one limitation. The house treats the Monday note as a craft object, not a screenshot dump.
Also in the catalogue
Shorter surveys.
Funnel Surveying
Diagnosing conversion collapse without padding the path. Includes a session on what not to put in a board funnel.
Identity Seams
Stitching anonymous to known without shredding historical cohorts. Dry, necessary, and rarely taught with this much caution.
From the journal
Recent field notes.
DAU is a coastline, not a score
A daily active number without a tide table is how boards get talked into a rescue that was never a wreck.
Event names that survive a reorg
If the verb belongs to a squad that will be renamed in autumn, the grid will lie by Christmas.
The house keeps office in Ponts Green.
Fees are listed without a checkout. If a survey fits your desk, write to us. If it does not, we would rather say so than fill a cohort.