Persistence & UX
Favorites — long-press any tab to pin it to a dedicated Favorites row
Last-used tab is remembered between launches
Search bar to filter calculators by name
Export/share button on several results (Speeds & Feeds, Tap Drill, Triangle Solver, Material Weight, Masonry, Fencing, Job Cost, Panel Load)
Settings screen with an appearance mode toggle — System / Light / Dark now genuinely change the color palette (previously "Light" didn't actually render light colors)
Optional one-time "tip" purchase in Settings for anyone who wants to support development — not a paywall, the app stays fully unlocked at your $5 one-time price
New trades calculators
Plumbing — pipe slope/fall, pipe volume & flow/fill time
HVAC — BTU heat load estimator, duct sizing
Electrical — new Panel/Service Load mode (whole-panel sizing via simplified NEC 220 method), added alongside your existing wire gauge, voltage drop, and conduit fill tools
Framing — stud count, deck joist span checker, deck board calculator
Masonry — block/brick + mortar calculator
Landscaping — mulch/soil/gravel volume, paver/patio calculator
Fencing — posts, rails, pickets, concrete
Job Cost Estimator — full quote builder (materials + labor + overhead + contingency + markup → final price and margin)