Tri vs GearTech OS
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Tri
This utility app provides the formula and value for calculating triangle properties. It's designed for quick access to mathematical formulas related to triangles.
- Triangle formula display
- Value calculation
- Quick access utility
- Mathematical formulas
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App to display a formula and value of a triangle.
GearTech OS
This app provides specialized calculation tools for various trades, including pipefitting, welding, electrical, and framing. It displays the math behind each result and generates real diagrams of what you're building. Works offline and is ad-free.
- Specialized tools for 10+ trades
- Detailed math for every calculation
- Real diagrams of built components
- Offline functionality
- Bilingual (English/Spanish)
- No ads or tracking
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GearTech OS replaces the box of single-purpose calculators in your truck with one app built for the trades — by someone who works them. Pick your trade and get tools made for it: pipefitting, welding, electrical, framing, concrete, HVAC, plumbing, machining, solar, sheet metal and automotive. No pipe jargon cluttering the electrician's screen, no electrical keys on the welder's — each trade gets its own tools and its own keypad shortcuts. EVERY result shows the math. Tap "Show math" under any answer to see the formula, your numbers plugged in, and the result. Learn it, trust it, and check your work in the field. REAL diagrams. Every tool draws what you're building — a 3D rolling offset box, a butt-weld elbow you can cut to a custom degree, a saddle/fishmouth, a reducer cone, roof rafters, conduit fill, ducts, gears and more. NEW — CRANE HAND SIGNALS IN 3D. 22 ASME B30.5 signals. The signal person gives the signal and the crane performs the motion, with the load always plumb. Spin the camera and watch it from wherever you have to stand. NEW — FLANGE BOLT-UP. Target-stress torque by bolt size, material, lubricant and percentage of yield, with the 30/60/100% passes worked out and the tightening order drawn for 4 to 32 bolts. Built for pipefitters and welders first: - Pipe offsets, rolling offsets, fishmouth/saddle templates, miters, trunnions, reducers (concentric & eccentric), and ASME B16.9 fittings with custom degrees - Spread/line banks, slope/grade, thermal expansion - Crane hand signals in 3D and flange bolt-up torque - Constants cheat-sheet and a 272-question practice EXAM for the NITC / UA STAR, including crane signal person — every question explained step by step, and the app remembers what you missed Plus 100+ tools across 10 more trades: - Electrical: voltage drop, conduit fill (NEC), box fill, ampacity + derating, motor FLC, 3-phase power, stub-up take-up - Framing: rafters, hip/valley/jack, stairs, pitch, baluster spacing, board feet - Concrete: slab/footing/column volume, bags, rebar, blocks - HVAC: tonnage, CFM, duct sizing (round & rect), friction rate, sensible BTU - Plumbing: drain slope, DFU, fixture units to GPM, pipe sizing, gas pipe - Machinist, Solar, Welding, Sheet metal, Automotive Works 100% offline — the 3D included. No account, no ads, no tracking. Your settings, cut lists and memories stay on your phone. Bilingual: English and Spanish, switch anytime. We build the world around us. Our tools should be built for us. — Per Diem Syndicate
Screenshots
Verdict
The clearest difference is ads: GearTech OS at none against Tri's shown. GearTech OS also leads on update cadence (every 5 days vs every 12 months) and monetization model (free vs ad-supported). On price, rating, review sentiment and in-app purchases there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
On the App Store both sit at effectively the same score — 5.0 for Tri against 5.0 for GearTech OS. That said, the two scores are not equally well evidenced: GearTech OS has 10 ratings behind it against 1, so its average is the more settled of the two. Written reviews split almost evenly too, at 100% and 100% positive.
Tri ships an update every 12 months, GearTech OS every 5 days. The most recent releases landed on October 20, 2026 and October 24, 2026 respectively.
| Parameter | Tri | GearTech OS |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (1 ratings) | 5.0 (10 ratings) |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| Number of ratings | 1 | 10 — better |
| Update frequency | Every 12 months | Every 5 days — better |
| Ads | Yes | No — better |
| In-app purchases | No | No |
| Monetization | Ad-supported | Free — better |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 15.6 — better | 16.0 |
| Further details — not scored | ||
| Size | 4 MB | 3 MB |
| Age rating | 4+ | 4+ |
| Developer | Thirdware.jp | Josue Ponce |
Customer experience
Tri
GearTech OS
In-app purchases
Tri
No in-app purchases
GearTech OS
No in-app purchases









