Comparison

Trades vs FlowLine Isometric

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Trades

Features
Read full description

The only app that replaces your Construction Master Pro AND gives you code-aware calculators for every trade — electrical, concrete, framing, plumbing, HVAC, and welding. All in one app. No subscriptions. Ever. TRY BEFORE YOU BUY Download free and get 1 working calculator from each of the 6 trade packs. No credit card. No time limit. See if it works for your job site before you spend a dime. WHAT'S INSIDE Electrical Pack — 11 Calculators Wire ampacity (NEC Table 310.16), voltage drop, conduit fill, box fill, motor circuit sizing, residential load calculation, transformer KVA, EVSE load, Ohm's law solver, parallel resistance, BTU-kWh converter. Edition-aware: NEC 2017, 2020, 2023, and 2026. Concrete Pack — 10 Calculators Slab volume, footing volume, minimum PSI by application (ACI 318-19 exposure classes), rebar spacing, footing size by soil bearing, water-cement ratio, concrete order calculator, post hole calculator, block/CMU wall, formwork estimator. Supports IBC 2018, 2021, and 2024. Framing Pack — 8 Calculators Rafter length with bird's mouth check, header sizing (IRC R602.7), board feet, stud count with California corners, floor joist span (IRC R502.3.1), roof pitch to angle with material minimums, stair stringer with IRC code checks, compound miter for crown molding. Supports IRC 2018, 2021, and 2024. Plumbing Pack — 9 Calculators Pipe sizing by flow, pressure drop (Hazen-Williams), DWV drain pipe sizing, water heater sizing, DFU count, thermal expansion, WSFU count, gas pipe sizing (IFGC), pipe offset with rolling offset support. Code-aware: IPC 2021/2024 and UPC 2021/2024. HVAC Pack — 10 Calculators BTU rule of thumb, CFM per room, duct sizing (equal friction), refrigerant charge (superheat and subcooling with R-454B, R-410A, R-32 support), static pressure, equipment tonnage, sensible heat ratio, SEER2 operating cost with DOE regional minimums, psychrometric calculator, gas pipe sizing for HVAC equipment. Based on ACCA Manual J 8th Edition. Welding Pack — 11 Calculators TIG/MIG amperage by thickness, stick (SMAW) amperage by electrode, wire feed speed, heat input (kJ/in per AWS D1.1), preheat temperature/carbon equivalent, shielding gas flow rate, filler metal selection with D1.1 prequalified status, fillet weld strength (ASD/LRFD), filler metal weight estimator, welding cost calculator, FCAW parameters. Supports AWS D1.1-2020 and D1.1-2025. REFERENCE TABLES INCLUDED Browse NEC, IRC, IPC, AWS, and ACI code tables right in the app. No flipping through codebooks. Tables include NEC 310.16 ampacity, IRC joist spans, IPC DFU values, AWS preheat tables, ACI exposure class requirements, and more. WHY TRADES: CALC? No subscriptions. Construction Master Pro charges $35/year. We charge once. All trades in one app. Stop juggling 5 separate apps on the job site. Code-aware. Pick your NEC edition (2017–2026). Toggle IPC vs UPC (2021/2024). Select your IRC year (2018–2024). Choose AWS D1.1-2020 or 2025. The app knows which code you're working under. Accurate. Every formula audited against primary code sources — NEC 2026, ACI 318-19, IRC 2024, IPC 2024, AWS D1.1-2025. Works offline. Every calculation runs locally. No internet required. No account required. PRICING Free — 1 calculator per pack (6 total) + browse the app Core Unlock ($9.99) — Full app + reference tables + choose 1 free trade pack Additional Packs ($6.99 each) — Add any trade you need All Access ($34.99) — Everything. All 59 calculators. All reference tables. All future content. Forever. All calculations are for reference only. Verify results with your AHJ and a licensed professional.

About

FlowLine Isometric

A professional tool for creating isometric piping diagrams. It allows pipefitters, plumbers, engineers, and contractors to quickly sketch and document pipe runs with a snap grid for precise isometric projection.

Highlights
  • Isometric projection drawing
  • Snap grid for precise lines
  • Quick sketching and documentation
  • On-site or office use
  • Focus on layout
Features
Read full description

Flowline is a professional isometric piping diagram tool built for pipefitters, plumbers, mechanical engineers, and contractors who need to sketch and document pipe runs quickly on site or in the office. Draw in true isometric projection with a snap grid that keeps every line on axis. Flowline handles the geometry so you can focus on the layout.

Screenshots

Trades4 screens
FlowLine Isometric4 screens

Verdict

The call

The clearest difference is in-app purchases: FlowLine Isometric at none against Trades's 8. Trades's advantage is iOS requirement (17.0 vs 26.0). On price, ads and device support 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Trades sells 8 one-off in-app purchases. FlowLine Isometric asks for nothing beyond the download.

Scorecard2 real differences · 7 level
Trades versus FlowLine Isometric: the parameters behind the verdict, then further details
ParameterTradesFlowLine Isometric
PriceFreeFree
Rating—4.0 (11 ratings) — better
Number of ratings—11 — better
Update frequency—Every 6 weeks
AdsNoNo
In-app purchasesYesNo — better
Monetization—Free
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.0 — better26.0
Further details — not scored
Size4 MB23 MB
Age rating4+4+
DeveloperPaul GregoryJoshua Parkin

In-app purchases

8 purchases

Trades

One-time8
  • Electrical Pack$6.99
  • Concrete Pack$6.99
  • Welding Pack$6.99
Show 5 more
  • Plumbing Pack$6.99
  • Framing Pack$6.99
  • HVAC Pack$6.99
  • App Unlock$9.99
  • All Access$34.99
None

FlowLine Isometric

No in-app purchases

Questions

Is Trades free?
Trades is free to download, with in-app purchases available.
Is FlowLine Isometric free?
FlowLine Isometric is free to download, with no in-app purchases.
Do Trades or FlowLine Isometric have ads?
Neither Trades nor FlowLine Isometric shows ads.

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