# Hide: Leathermaker's Calc — Saddle-stitch math. Cited.

> Saddle-stitch math. Cited. (iPhone/iPad app by Roman Kopaliani.)

- Source: https://appshunter.io/ios/app/hide-leathermakers-calc/id6778773369 (this page in markdown: same URL + `.md`)
- Developer: [Roman Kopaliani](https://appshunter.io/developer/1635315269)
- Category: Utilities, Lifestyle
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 17.0 · 1 MB
- Languages: American English
- Released: 2026-06-16
- Data updated: 2026-08-20
- User reviews in markdown: https://appshunter.io/ios/app/hide-leathermakers-calc/id6778773369/reviews.md

## What is Hide?

Hide is a leatherworking calculator with cited math. Every SPI, every thread-length rule, every edge-finish recommendation names its source. Pay once at $6.99 for Hide Pro — no subscription, no ads, no scanner.

The wedge

Most leatherworking apps stop at thread length. Hide includes thread length in the free tier (matches the incumbent's full surface) and unlocks the rest with one $6.99 lifetime purchase: saddle-stitch SPI by leather weight × project, edge-finish recommendation by leather temper, glue selection by use case, dye + sealant by goal, brand-aware presets. Every method tells you whose method it is.

Free tier

• Thread-length calculator — Stohlman's precision rule and Armitage's generous heuristic, side-by-side, with the leather-thickness math shown
• Leather weight oz → mm thickness conversion (1 oz ≈ 0.4 mm per Tandy convention)
• 1 saved project slot
• Brand picker showing the supplier names

Hide Pro ($6.99 lifetime)

• Saddle-stitch SPI by leather weight × project type, with awl-hole spacing in mm / inches
• Edge-finish matrix — burnish with water + gum tragacanth, burnish + Tokonole wax, edge paint, or wax burnish — selected by leather temper (veg-tan smooth, veg-tan thick, chrome-tan, bridle, oil-tan)
• Glue selection matrix — contact cement vs EVA white vs PVA vs hide glue — by use case + dry time + odor
• Dye + sealant matrix — spirit / oil / water dye, Resolene / acrylic / wax sealant, with compatibility warnings
• Brand-aware presets: Tandy Leather, Buckleguy, Maverick Leather, Wickett & Craig, Horween — typical SKU ranges + edge-finish recommendation per their leather chemistry
• Unlimited project log
• Citations & Sources screen with every author named

Honest authority story

Leatherworking has no USDA / AOCS / Knife Steel Nerds equivalent. Hide's authority is practitioner-tier, and we own that: Al Stohlman (The Art of Hand Sewing Leather, Tandy 1977), Nigel Armitage (Armitage Leather, UK), Stitchpunk (J.H. Sherman), Corter Leather & Cloth (Eric Heins), plus tannery technical sheets from Wickett & Craig, Horween, and Sedgwick & Co. Every number Hide displays tells you whose method it is so you can verify against the original.

The Moon Dog promise

• Pay once. No subscription. No ads.
• No account. No login. No signup. No network.
• Works fully offline.
• No data collection.

Disclaimer

Hide is for hobby leatherworking guidance. Independent verification against your supplier's technical sheets and your own project requirements is your responsibility.

© 2026 Roman Kopaliani

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Hide Pro (lifetime) | $6.99 | one-time |



## Version history (last 3 releases)

### 1.2 — 2026-08-15

Maintenance update. No feature changes.

### 1.1 — 2026-07-16

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.

### 1.0 — 2026-06-17

No release notes.

## More apps by Roman Kopaliani

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All apps by Roman Kopaliani: https://appshunter.io/developer/1635315269

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-20.*