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Card 414 of 9992026-08-20 issue

Observed arrival · 2026-08-20

Inkerval Makes Math Practice Feel Like a Notebook

Editorial interest 78/100 Selection signal · not a rating of the site

An iPad and Apple Pencil app for handwritten university-math practice, covering probability and differential equations.

Landing page captured for the 2026-08-20 issue.

Why it surfaced

Inkerval combines handwritten problem solving with a self-assessed spaced-repetition system: solve by hand, mark the attempt as solved or shaky, and let the app decide what returns tomorrow. Its launch plan is unusually concrete, with 400+ probability problems and 300+ differential-equations problems, all presented as verified practice rather than multiple-choice drills.

An iPad and Apple Pencil app for handwritten university-math practice, covering probability and differential equations.

Observed signals

Read the marks

Editorial observations of this landing page, not a rating.

OpenPublic substance visible
PrettyNotable craft visible
ProPolished or operationally mature
NicheUnusually specific use

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The Law, Drawn by Hand

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inkerval.com

Landing page observed 2026-08-20. The live site may have changed.