SketchCalc
Visual computation, handwriting, graphs and vector thinking
Calculate
like you sketch.
SketchCalc 1.0.33 is available on the App Store and Google Play.
A local-first visual calculation workspace that combines linked arithmetic, exact scientific math, CAS Lite, calculus, matrices, handwriting recognition, charts, function graphing, geometry, Vector CAD, templates, and project export inside one connected canvas.
Local-firstNo account requiredFree + one-time PROiPhone · iPad · Android
✦✎
See the workflow
SketchCalc in action.
This walkthrough shows the spatial calculation concept: numbers, notes, linked results, sketches, and visual logic working together on one page. The current v1.0.33 release extends that foundation with the advanced systems documented above.
An applied visual computing product
More than a calculator, and more connected than a notes app.
SketchCalc treats calculations as visual objects that can be placed, labelled, linked, graphed, drawn around, reorganized, and exported. Version 1.0.33 brings the original spatial-calculation idea together with exact arithmetic, symbolic tools, calculus, matrices, deterministic handwriting interpretation, and editable vector geometry.
Complete v1.0.33 feature reference
Every major system, from the first number to the final export.
The sections below describe the actual current product scope, including Free and PRO boundaries and deliberate limitations. SketchCalc avoids claiming capabilities that are outside its bounded local engines.
01
Spatial calculation canvas
- Place numbers, operators, results, notes, graphs, sliders, artwork, and drawings directly on a flexible page instead of forcing every idea into one calculator line.
- Move blocks around the canvas, continue from an earlier result, reorganize a calculation visually, and keep context close to the numbers.
- Copy an object, copy it as text, paste clipboard content, edit values, delete items, and use undo or redo while the page evolves.
- Add labels above values, create freeform text notes, adjust note size and emphasis, and switch between light and dark appearance.
02
Linked calculations and reusable results
- Link an editable number or calculated result to another location and reuse it as an input without manually retyping the value.
- When the source changes, linked calculation groups can refresh so scenario chains remain connected and easier to audit.
- Use ANS, calculation history, exact-answer copy, and memory controls M+, M−, MR, and MC for repeated work.
- Continue calculating from an existing result by selecting it and adding the next operation directly on the page.
03
Exact arithmetic and scientific calculator
- Supports addition, subtraction, multiplication, division, parentheses, percentages, negative values, powers, and factorials.
- Includes square root, cube root, configurable n-th root, π, e, absolute value, logarithm, and natural logarithm.
- Includes sine, cosine, tangent, inverse trigonometric functions, explicit degree input, and switchable DEG/RAD modes.
- Retains exact rational values internally when an expression permits it, while still providing numerical results when approximation is required.
- Copy an exact answer or a fraction representation instead of being limited to a rounded display value.
04
Smart Paste, variables, units, and practical math
- Paste ordinary expressions, labelled calculations, text, links, or multiple variable definitions directly into the workspace.
- Create reusable variables such as rent = 1200 or tax = 8.25%, then reference those names in later expressions on the same page.
- Understands practical patterns for percentages, discounts, tips, tax, splitting a total, monthly division, and simple dates from today.
- Converts compatible length, mass, area, volume, speed, and temperature units, including km/mi, kg/lb, cm/in, ft/m, square feet/square metres, litres/gallons, mph/kmh/m/s, and °C/°F.
- When clipboard text is not a valid mathematical expression, SketchCalc can preserve it as a note instead of discarding it.
05
CAS Lite symbolic workspace — PRO
- Simplify algebraic expressions, expand products, factor supported rational polynomials, and substitute values into expressions.
- Solve supported first-degree and second-degree equations and exact 2×2 linear systems.
- Copy the result, insert it into the page, and save useful formulas for later reuse.
- CAS Lite is intentionally bounded. It does not claim unrestricted symbolic integration, complex algebra, arbitrary high-degree solving, or full desktop-CAS coverage.
06
Calculus workspace — PRO
- Calculate symbolic derivatives and numerical derivatives at a selected x value.
- Run safe symbolic integration and numerical definite integration between user-defined bounds.
- Evaluate limits, finite sums, roots inside a range, and minimum or maximum values inside an interval.
- Copy a result, add it to the current page, or create a Function Graph directly from the working expression.
- Calculus trigonometric functions use radians, and unsupported symbolic cases return bounded errors rather than invented results.
07
Matrix tools — PRO
- Calculate determinant, inverse, and transpose operations locally.
- Add two matrices or multiply compatible matrices.
- Enter matrices as editable rows and columns, review the result, copy it, or add it to the workspace.
- Matrix actions are also available as destinations from the Handwriting Math V2 workflow.
08
Data Charts
- Create line, bar, or scatter charts directly on the page.
- Use multiple named series, editable titles and descriptions, X and Y axis labels, and resizable chart cards.
- Validate structured chart data before saving; invalid rows stay visible for correction instead of silently disappearing.
- Use comma-separated values or semicolon-separated rows when decimal commas are needed.
- Free includes one Data Chart. PRO unlocks unlimited graph cards.
09
Function Graph — PRO
- Plot up to six functions of x in one graph card, with one function per line.
- Set the X range and optionally define a manual Y range.
- Overlay the derivative of the first function and shade the integral area between selected bounds.
- Create a graph from the Calculus workspace or route reviewed handwriting directly into Function Graph validation.
- Function Graph trigonometric expressions use radians.
10
Handwriting Math V2 — PRO
- Write with a finger, Apple Pencil or compatible stylus, mouse, or trackpad. Pressure-aware strokes are retained where the platform provides pressure data.
- Recognizes digits, basic operators, parentheses, x/y, square-root forms, exponent placement, integral and sigma candidates.
- Supports multi-line input, systems, matrix-style rows, and nested fraction layouts up to three recursive levels.
- Shows recognition confidence and editable output so a user can correct ambiguous symbols before anything runs.
- Route reviewed text to Calculate, CAS simplify, equation/system solving, derivative, symbolic integral, definite integral, finite sum, Matrix, or Function Graph.
- Recognition never changes the workspace automatically. Adding a result or graph always requires a second explicit user action.
- The recognizer is deterministic and on-device; it is not presented as a general-purpose cloud OCR service.
11
Drawing and geometry tools
- Create lines, circles, ellipses, squares, rectangles, triangles, polygons, and stars.
- Move, resize, and rotate drawings; edit exact X/Y position, width, height, diameter, line endpoints, rotation, and stroke width.
- Adjust square or rectangle corner radius, polygon side count, star point count, and star inner ratio.
- Mirror geometry on X or Y, lock objects against accidental editing, duplicate drawings, and use an optional 5- or 10-unit snap grid.
- Basic geometric tools remain available in Free.
12
Vector CAD and path editing — PRO
- Draw freehand strokes, click-or-drag Pen paths, and Bezier paths.
- Open or close a path, enter anchor-editing mode, move anchors and handles, add or delete anchors, and switch a point between corner and curve behaviour.
- Multi-select drawings, align left/centre/right or top/middle/bottom, and distribute three or more objects horizontally or vertically.
- Combine supported closed shapes with Union, Subtract, Intersect, or Exclude/XOR Boolean operations.
- Locked or unsupported open paths are protected from destructive Boolean actions.
13
SVG import and vector export — PRO
- Open a local SVG file and review a supported/unsupported element summary before the current page changes.
- Imported SVG geometry is added to the current page without clearing existing calculations or drawings.
- Export selected drawing objects as SVG or export the full drawing layer from the current page.
- Unsupported SVG features are reported. Complex arc commands, text, gradients, masks, raster images, and unsupported mixed structures are not silently treated as fully compatible.
14
Live scenario sliders — PRO
- Attach a slider to an editable input number and define minimum, maximum, step, and control width.
- Move the slider to update the source input and connected calculations for live what-if exploration.
- Calculated Result blocks are protected from direct control; create or link an editable input number when a scenario needs a slider.
- Sliders are included in page rendering and supported exports.
15
Pages, templates, and project organization
- Free provides one active page with 18 calculation rows and includes the Apollo 11 visual walkthrough template.
- PRO expands the workspace from an 80-row base as projects grow and supports multiple pages.
- Add, rename, duplicate, delete, and switch between pages to separate project stages or topics.
- PRO templates include Budget Planner, Tip & Split, Loan Snapshot, Profit Margin, Investment Growth, and Unit Conversion.
- Load a template by replacing the current page or creating it safely on a new page.
16
Export, import, and recovery — PRO
- Free can copy the current page as plain text.
- PRO can copy all pages as text and export selected pages to PDF using Fit to page, Landscape, or Split into pages layouts.
- Export the current page to PNG using a local destination picker.
- PDF and PNG rendering includes calculations, notes, chart cards, sliders, Apollo artwork, and Drawing/CAD objects rather than text-only placeholders.
- Copy the complete project as JSON, import project JSON from the clipboard with a preview and confirmation step, and restore the automatic backup created before the last import.
- File operations use user-selected local destinations; the workflow does not require an email or developer-server upload.
17
Local-first persistence and privacy
- Calculations, handwriting recognition, CAS, Calculus, Matrix, charts, drawings, and project files are processed locally.
- No account or sign-in is required, and project content is not uploaded to a developer-operated SketchCalc server.
- Workspace writes use staged, validated, atomic local files with rotating backups and migration from older storage where applicable.
- The Free version can display Google Mobile Ads after the applicable consent flow. The one-time PRO purchase removes the banner and unlocks advanced tools.
- Apple and Google handle store payments; SketchCalc does not receive full payment-card details.
18
Touch, keyboard, theme, and accessibility
- Designed for phone and tablet touch interaction with a compact toolbar, sketch-style keypad, draggable blocks, and responsive dialogs.
- Supports light and dark modes and layouts tested across compact widths and enlarged text settings.
- Keyboard shortcuts include Enter or = to calculate, Backspace to remove a token, Escape to cancel an active path, and standard copy, paste, undo, and redo shortcuts.
- Pen and Bezier paths can be finished with Enter, closed with Shift+Enter, or cancelled with Escape on supported hardware.
Clear product boundariesCAS Lite is a bounded symbolic tool rather than an unrestricted desktop CAS. Handwriting Math V2 is a deterministic on-device recognizer rather than general-purpose OCR. Every recognized expression remains editable, and no recognition result executes automatically.
One app, two levels
Start with the full visual idea. Unlock advanced project systems with PRO.
SketchCalc is one application. Everyone downloads the same app; the optional one-time PRO purchase removes banner advertising and unlocks the advanced systems already built into the product.
For quick visual calculations
- One active page and 18 calculation rows
- Spatial calculation canvas with movable numbers, results, notes, and links
- Exact arithmetic and scientific functions, including DEG/RAD modes
- Smart Paste, variables, practical percentage patterns, dates, and unit conversion
- One editable Data Chart
- Basic geometry and drawing tools
- Apollo 11 Demo template
- Copy current page as text
- Ad-supported workspace after applicable consent choices
For deeper mathematical and project workflows
- Expandable workspace and multiple pages
- Unlimited graph cards, sliders, and templates
- CAS Lite, Calculus, Matrix, and Function Graph
- Handwriting Math V2 with review-first workflow routing
- Freehand, Pen, Bezier, anchors, alignment, distribution, and Boolean vector tools
- SVG import and selected/full-layer SVG export
- PDF, PNG, all-page text, and project JSON export/import
- Automatic pre-import backup restore
- No banner advertising
Product development and technical validation
A continuously expanded system, not a static prototype.
SketchCalc progressed from an early spatial calculator into a modular cross-platform visual computation product. The public page documents that evolution because the engineering, interaction design, privacy architecture, and release validation are part of the product itself.
v1.0.28
Exact and symbolic foundations
Exact rational arithmetic, expanded scientific tools, DEG/RAD handling, roots, constants, and bounded CAS Lite.
Exact rational arithmetic, expanded scientific tools, DEG/RAD handling, roots, constants, and bounded CAS Lite.
v1.0.29
Advanced mathematical workspaces
Calculus, Matrix operations, and multi-function graphing with derivative overlay and integral-area shading.
Calculus, Matrix operations, and multi-function graphing with derivative overlay and integral-area shading.
v1.0.30
Local handwriting input
Pressure-aware ink capture, deterministic symbol recognition, confidence, alternatives, fractions, exponents, and review-first actions.
Pressure-aware ink capture, deterministic symbol recognition, confidence, alternatives, fractions, exponents, and review-first actions.
v1.0.31
Handwriting Math V2
Nested fractions, multi-line recognition, matrix/system rows, integral and sigma candidates, and unified routing into existing engines.
Nested fractions, multi-line recognition, matrix/system rows, integral and sigma candidates, and unified routing into existing engines.
v1.0.33
Production integration
App Store and Google Play release work, Android advertising and purchase support, user-selected file workflows, signing safeguards, responsive QA, and final packaging.
App Store and Google Play release work, Android advertising and purchase support, user-selected file workflows, signing safeguards, responsive QA, and final packaging.
Where it fits
Designed for work that mixes numbers with visual context.
SketchCalc is useful when the calculation is only one part of the thinking process and the surrounding labels, comparisons, geometry, diagrams, or scenarios matter too.
Design planningProject estimatesRoom measurementsBudgets and marginsClient calculationsScientific studyFunction explorationEngineering notesUnit conversionWhat-if scenariosVisual problem solvingReusable project boards
Free browser demo
Try the free SketchCalc workspace.
This browser demo is a compact preview of the core spatial canvas. It demonstrates the Free workflow: one active page, an ad-supported workspace, movable calculation blocks, notes over values, linked results, and continued calculations. Advanced v1.0.33 systems such as CAS Lite, Calculus, Matrix, Function Graph, Handwriting Math V2, Vector CAD, templates, and file export are available in the mobile app.
Calculate on the page
Tap the canvas, enter 12 x 3 =, then select the result and continue with + 4 =.
Notes over values
Select a number or result and press Note to attach context directly above that value.
Free mode visible
Page 2 is locked and the ad banner remains visible, matching the free app flow.
Build the calculation on the page.
Download SketchCalc free on the App Store or Google Play. Upgrade once inside the app when your work needs the complete mathematical, handwriting, vector, project, and export toolset.
Support
Questions, feedback, or privacy requests?
For app support, purchase or restore questions, technical feedback, accessibility feedback, store-review contact, or privacy requests, email creatooo.com@gmail.com.
Privacy
SketchCalc Privacy Policy
Effective date: July 16, 2026
Last updated: July 16, 2026
SketchCalc is a visual calculation workspace for notes, calculations, graphs, drawings, handwriting, and spatial math organization. This Privacy Policy explains how information is handled when you use SketchCalc on Apple or Android devices.
Information handled directly by SketchCalc
SketchCalc does not require an account. We do not directly collect or store names, email addresses, phone numbers, contacts, precise location data, health information, photos, videos, audio recordings, payment-card details, or user-created project content on our own servers. SketchCalc does not operate a server that receives the contents of your calculations, notes, pages, drawings, graphs, handwriting strokes, or exported files.
Local workspace data
Calculations, notes, pages, drawings, graphs, handwriting recognition, project files, and exported PDF, PNG, SVG, text, or project data are stored, processed, or generated locally on the user’s device. Files are transmitted to another service or person only when the user intentionally selects a system sharing, saving, exporting, or backup action.
Advertising and Google AdMob
The Free version uses Google AdMob to display advertisements. The Google Mobile Ads SDK may process information such as IP address and approximate location, app and advertisement interactions, diagnostic and performance information, advertising identifiers, app-set identifiers, and comparable device identifiers for advertisement delivery, measurement, analytics, security, fraud prevention, and diagnostics. SketchCalc does not intentionally send the contents of user calculations, notes, drawings, graphs, handwriting, projects, or exported documents to Google AdMob. Information processed by Google is subject to the Google Privacy Policy.
Advertising consent and privacy choices
Where required by law, SketchCalc or Google’s consent system may ask users to make privacy and advertising choices before advertisements are requested. Available privacy controls may vary by device, operating system, location, and platform requirements. Users can also manage advertising preferences through their device settings and Google or Apple privacy controls.
In-app purchases
SketchCalc offers a one-time PRO upgrade through the Apple App Store or Google Play. Payments are processed by Apple or Google. We do not receive or store full payment-card numbers or banking credentials. The store may provide limited information such as product identifier, purchase status, transaction or receipt information, and data required to unlock or restore PRO access.
Diagnostics and performance
SketchCalc and platform services may process crash reports, diagnostic information, device information, app-version information, and performance data to identify technical issues, improve stability, maintain compatibility, and protect app and advertising systems against abuse or fraud.
Data sharing
We do not sell the contents of user-created calculations, notes, pages, drawings, graphs, handwriting, projects, or exported documents. Limited device, advertising, interaction, diagnostic, purchase, or performance information may be processed by Google AdMob, Google Play, the Apple App Store, and platform diagnostic services according to their own terms and privacy policies.
Retention and deletion
Local workspace content remains on the device until the user deletes it, clears app data, uninstalls the app, or replaces the device without preserving a backup. Because SketchCalc does not maintain user accounts or store workspace content on its own servers, we normally cannot remotely access, recover, or delete local workspace content. Advertising, purchase, and diagnostic providers may retain information according to their own policies.
Children’s privacy
SketchCalc is a general productivity and visual calculation app. It is not designed specifically for children, and we do not knowingly collect personal information directly from children.
Data security
SketchCalc is designed to keep user-created workspace content locally on the device. Data transmitted to third-party services uses the security and encrypted communication methods provided by those services. No storage or transmission system can be guaranteed to be completely secure.
User choices and rights
Depending on location, users may have rights relating to personal data, including rights to request information, object to certain processing, withdraw consent, or request deletion. Most SketchCalc workspace data can be managed directly on the device through in-app actions, device privacy and advertising settings, clearing app data, or uninstalling SketchCalc.
Changes to this policy
We may update this Privacy Policy when SketchCalc features, service providers, legal requirements, or data-handling practices change. Updates will be posted on this page with a revised date.
Contact
For privacy questions, data-related requests, or concerns, contact creatooo.com@gmail.com.