• All six soap qualities — hardness, cleansing, conditioning, bubbly, creamy, longevity — are now free forever. They were behind Pro; they shouldn't have been. • New in Pro: cost per bar. Price your oils once and Trace costs every batch, then divides by your bar weight. • The paywall, the trial banner and the upgrade screens are now translated — they were English-only in every language.

• The free trial now runs for 7 days of actual use — days you don't open Trace don't count against it • Everyone gets a fresh 7-day trial with this update, so you can pick up where you left off • Trial time remaining is now shown in days

• Corrected citric acid lye adjustment to the stoichiometric 0.624 g NaOH (0.876 g KOH) per gram of citric acid — if you use citric acid, please recalculate saved recipes • Liquid-soap (KOH) recipes with citric acid now adjust KOH, not NaOH • Ounce display now works everywhere • Water input resets to a sensible default when switching modes • Trial countdown shown; cure length adjustable per batch

Behind-the-scenes improvements for a smoother, faster app.

The number keyboard now has a Done button, so you can dismiss it when you're finished. Thanks to everyone who wrote in about this.

Trace is now free to calculate. The full lye calculator — every oil, NaOH / KOH / dual-lye, water expressions, IFRA fragrance caps and additive math — is unlocked for everyone, no purchase needed. Trace Pro (one-time, no subscription, no ads) adds saved recipes, quality analysis, branded oil presets and the multi-batch cure tracker. Happy soaping.

New: the More from Moon Dog list in Settings now points to sibling maker's calculators — candles, cheese, leather and knives. Plus reliability improvements. Happy soaping.

Trace is now free to download with a full 48-hour trial — try the SAP calculator, oil database, and cure tracker with no commitment. After the trial, unlock everything forever with a single purchase. No subscription, no ads. Already bought Trace? You keep full access automatically.