Comparison

STEP Viewer vs STP One

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

Head to head
About

STEP Viewer

View and interact with 3D CAD files directly on your mobile device. Measure dimensions, rotate, zoom, and save models in a common format without needing desktop software.

Highlights
  • Open STEP files from file manager
  • 3D model measurement tools
  • Six fixed views
  • Pinch to zoom, pan, and rotate
  • Save as GLB
  • Progress indicator for large files
  • Multilingual support
Features
Read full description

STEP Viewer opens STEP (.step, .stp) CAD files in 3D on your phone. No desktop CAD software needed. Everything is free. There are no in-app purchases. Credits only skip the ad; without credits you can still open every file after watching a short ad. Key features * Open .step and .stp files straight from your file manager - just tap the file * Measure your model: a bounding box with all three side lengths, in mm or m * Six fixed views (front, right, back, left, top, bottom), plus pinch to zoom, pan and rotate * Save the converted model as GLB whenever you need it * Large files show the estimated time and memory before conversion starts, and progress while it runs * If a file cannot be opened, the app tells you why instead of failing silently * Available in 12 languages, following your device settings Supported formats * Input: .stp, .step (STEP AP203, AP214) * Output: .glb (glTF Binary) How to use 1. Tap a .step file in your file manager, or open the app and tap the folder icon 2. Wait for the conversion - large files show progress and an estimate 3. Drag to rotate, pinch to zoom, tap the view button to switch sides License This app uses Open CASCADE Technology (LGPL-2.1). https://www.opencascade.com For questions or bug reports, please contact us by email.

About

STP One

Features
Read full description

STP One is a drawing viewer built for the shop floor: open STEP and IGES 3D files and 2D drawings (DXF) right on your phone. The overall size (W×D×H) appears as soon as a file opens, and measurement, section, parts and weight are all in one app. ■ 3D viewing · Open STEP (.stp/.step) and IGES (.igs/.iges) · One finger to rotate, two fingers to pan and zoom, [Fit] to recenter · Overall dimensions shown automatically, plus approximate volume and surface area · Edge highlight: normal → bold → hidden ■ Measurement (Pro) · Point-to-point distance with ΔX · ΔY · ΔZ · Point→edge perpendicular distance · Face↔face distance between two parallel faces, with the angle between them ■ Section & parts (Pro) · Section along X/Y/Z — move the slider to cut the model and see inside, flip direction · Assembly parts list — each part cycles visible → transparent → hidden ■ Weight (Pro) · 245 built-in materials (steel sheet, stainless steel, non-ferrous metals, spring wire, injection resins, rubber and more) · Pick a material and get the weight from the model volume instantly ■ 2D drawings (Pro) · Open 2D drawings (DXF) — one finger to pan, two to zoom · Export a print-ready A4 PDF and share it by message or e-mail ■ Handy extras · Reopen your 5 most recent files · Open drawings sent from other apps · 7 languages: 한국어 · English · 中文 · Español · Tiếng Việt · हिन्दी · नेपाली ■ Private, on-device processing · Drawing viewing and calculations run on your device; drawings are not uploaded automatically · Your original files are never modified · No sign-up, no ads, no internet connection needed to view drawings ■ Free and Pro · Free: 1 file per day — 3D view, rotate, overall size, edge highlight · Pro subscription (monthly/yearly): unlimited files + measurement, section, parts, weight, 2D drawings and PDF sharing · Every Pro feature can be tried 3 times for free before you subscribe · Subscriptions renew automatically unless cancelled at least 24 hours before the end of the period; manage or cancel anytime in your store account settings Whenever you need to check a drawing in manufacturing, design, sales or quality, it is ready the moment you install it. Developed by LIHAON Co., Ltd., an automotive parts manufacturer. Optional ERP feedback lets existing LIHAON employees verify their employee ID/name and submit request text, comments and app/device details to the company ERP. Drawings are not attached automatically. Reading drawings requires no employee account. Subscription validation/restoration uses the internet. Privacy: https://erp.lihaon.co.kr/privacy-stpone EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

STEP Viewer4 screens
STP One4 screens

Verdict

The call

The clearest difference is in-app purchases: STEP Viewer at none against STP One's 2. STEP Viewer also leads on iOS requirement (13.0 vs 16.4). On price, update cadence, 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. STP One sells 2 in-app purchases, starting at $9.99 per month. STEP Viewer asks for nothing beyond the download.

UpkeepUpdate frequency

STEP Viewer ships an update every 5 days, STP One every 6 days. The most recent releases landed on October 30, 2026 and November 10, 2026 respectively.

Scorecard2 real differences · 7 level
STEP Viewer versus STP One: the parameters behind the verdict, then further details
ParameterSTEP ViewerSTP One
PriceFreeFree
Rating1.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyEvery 5 days — betterEvery 6 days
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better16.4
Further details — not scored
Size61 MB13 MB
Age rating4+4+
DeveloperSmart Cube Labs Co., Ltd.JAEYUN HWANG

In-app purchases

None

STEP Viewer

No in-app purchases

2 purchases

STP One

Subscriptions2
  • 스텝원 Pro 월간7 Days trial$9.991 Month
  • 스텝원 Pro 연간7 Days trial$69.991 Year

Questions

Is STEP Viewer free?
STEP Viewer is free to download, with no in-app purchases.
Is STP One free?
STP One is free to download, with in-app purchases available.
Do STEP Viewer or STP One have ads?
Neither STEP Viewer nor STP One shows ads.
Which is updated more often, STEP Viewer or STP One?
STEP Viewer ships an update every 5 days, and STP One every 6 days. Most recently, STEP Viewer was updated on October 30, 2026 and STP One on November 10, 2026.

Other comparisons