Apps by Armchair Engineering
Rafter Help app icon

Utilities

Rafter Help

Armchair Engineering

$1.99 4.61 · 7 storefronts · 628 ratings In-app purchases
Open on Apple

About this app

Rafter Help is the easiest way to calculate rafter length and associated values when building! Quickly find roof pitch, rafter lengths and ridge height for gable roofs, based on room and ridge width.  Or calculate length values with more control from the Advanced tab. Features Include: - Accurately solve rafter equations - Enter pitch steepness in radians, decimal degrees or degrees, minutes, seconds (DMS) or rise/run (e.g. 8/12) - Enter lengths in mm, cm, inches or feet - Select your preferred number of decimal places

Latest release

What’s New

Version 1.5.2 Nov 8, 2019

- Fixed floating keyboard bug, present on some devices running iOS 13

Audience growth

Ratings growth

Steady
7-day gain +0
Ratings / day 0.0
30-day gain +0
US rating-count history
212 ratings
212 Aug 7, 2026 · 212 ratings Aug 7, 2026

Baseline captured. Growth appears after the crawler observes a changed rating count.

Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.

Price tracking

Price intelligence

1 captured event
Current $1.99
Historical low USD 1.99
Paid → free
Price history
Current $1.99
$1.99 $1.00 Free Aug 7, 2026 · $1.99 Aug 12, 2026 · $1.99 Aug 7, 2026 Aug 12, 2026
  1. First observed Aug 7, 2026 · 10:43 PM $1.99

Screenshots

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