About this app
You can use this app to calculate the heating load for a simple rectangular building of brick/block or sheet construction under a pitched roof with natural air infiltration only. Calculations can then be saved for future reference or emailed.
Latest release
What’s New
This update from Apple will improve the functionality of this app. No new features are included. Updated logo.
Audience growth
Ratings growth
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
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 27, 2026 · 4:15 AM Free
Screenshots
