Causal Loop Diagram

"Causal Loop Diagram" is a fast, focused editor for sketching causal loop diagrams (CLDs) on iPhone — a foundational tool of systems thinking. Place variables, draw arrows, set polarities (+/−), and the app automatically detects feedback loops and classifies the whole diagram against well-known systems-thinking archetypes. — Features — ■ Simple drawing • Tap empty area to add a node, then tap source → target to link • Long-press an arrow to add a delay marker (||) • Drag nodes freely; pinch to zoom; one-finger drag on empty area to pan ■ Automatic loop detection • The moment a cycle closes, an R (reinforcing) or B (balancing) badge appears • Each loop is numbered (R1, R2, B1, B2…) so overlapping loops stay distinguishable • Tap a badge to highlight that loop's interior; other loops dim ■ Nine archetypes auto-classified • Reinforcing loop / Balancing loop • Limits to Growth • Fixes that Fail • Shifting the Burden • Escalation • Success to the Successful • Tragedy of the Commons • Growth and Underinvestment ■ Seven curated samples Familiar themes — study, family, sibling rivalry — to learn each archetype by example: • Study Habit (R) • Calibrating to Target Score (B) • Limits to Growth: Fatigue • Shifting the Burden: Escapism • Fixes that Fail: All-nighter • Escalation: Sibling Rivalry • Tragedy of the Commons: Parent's Attention ■ Privacy • No network access at all • No account, no sign-in • No analytics or tracking SDKs • Diagrams stored only in UserDefaults; uninstalling removes everything ■ Other • Japanese / English UI, one-tap switch • Save multiple diagrams locally with custom names • iOS 16+ (iPhone 8 and later) — Who is this for — • Students of systems thinking and system dynamics • Managers and designers who think in structures • Anyone who wants to step back and see the loops in their own habits, relationships, or work • Educators preparing diagram examples on the fly Pairs naturally with Peter Senge's "The Fifth Discipline" and other systems-thinking textbooks — turn the loops in your head into something you can draw and touch in seconds.