RetroBuild is a fast, visual structural engineering tool for analysing beams and columns right from your phone. Whether you're an engineering student checking homework, a site
engineer doing a quick sanity check, or a professional exploring "what-if" scenarios, RetroBuild gives you instant, clear results — no spreadsheets required.

REAL-TIME BEAM SIMULATOR
Adjust span, load type, magnitude and position and watch the results update live:
• Support reactions
• Bending moment and maximum moment
• Deflection and maximum deflection
• Bending stress
• Safety factor against your chosen material

COLUMN ANALYSIS
Check columns under axial load with selectable cross-sections and load presets, and see how section size affects capacity.

MATERIAL DATABASE
Pick from a built-in library of modern and heritage materials, each with compressive strength, density and elastic modulus. Add your own custom materials to match the exact specs
you work with.

SAVE YOUR PROJECTS
Save any configuration as a named project and reopen it later. Each project keeps its beam, load, section and material details — and the calculated results — so you can compare
designs and pick up where you left off.

EXPORT TO PDF
Generate a clean PDF summary of your analysis to share with colleagues, attach to reports, or keep for your records.

CLEAR, MODERN DESIGN
A focused dark interface with smooth, interactive controls puts the numbers that matter front and centre.

WHO IT'S FOR
• Civil and structural engineering students
• Practising engineers needing quick checks
• Builders, designers and educators

RETROBUILD PRO
Upgrade once to unlock unlimited saved projects. It's a single one-time purchase — no subscriptions, no ads.

WORKS OFFLINE
All calculations run on your device. No account, no internet connection required to use the app.

A NOTE ON ACCURACY
RetroBuild is intended as an educational and preliminary-design aid. Results should always be verified against applicable codes and reviewed by a qualified engineer before being
used for construction.

Download RetroBuild and turn your phone into a pocket structural lab.

A few notes:
- The full description above is ~2,050 characters — comfortably under the limit, with room to add anything specific (units supported, standards referenced, etc.).
- I included a disclaimer paragraph — for an engineering/calculation app this both protects you and tends to sit better with reviewers.
- If "heritage materials" or any feature I listed isn't actually exposed in the UI, tell me and I'll trim it so the listing stays accurate (Play penalizes mismatches between
listing and app).