O vs MechTab
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
O
This app helps users calculate O-Ring dimensions and find compatible materials for their applications. It provides recommendations based on ISO standards and supports both metric and inch measurements.
- O-Ring housing calculation
- O-Ring size recommendations by ISO standard
- Quick search by national/international standards
- O-Ring tolerance calculation
- Metric and inch unit switching
- Chemical compatibility check
- Integration of Trelleborg Sealing Solutions Videos
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The Trelleborg Sealing Solutions O-Ring App calculates O-Ring dimensions by simply entering installation specifications for your application in metric or inch. In addition, the App recommends O-Ring sizes according to ISO 3601 so you know exactly which part you need. Features at a Glance: - O-Ring Housing: After entering the bore or rod/shaft diameter, you will receive an O-Ring recommendation and O-Ring housing calculation according to the recommendations of ISO 3601 - O-Ring Quick Search: offers the selection of O-Ring nominal sizes according to the following national/international standards: ISO 3601-1 Class B (International), ISO 3601-1 Class A (AS 568, USA), NFT 47-502 (France), JIS B 2401 (Japan) SMS 1586 (Sweden) - Tolerances: calculation of O-Ring tolerances according to ISO 3601-1 Class B and Class A - Switch between metric and inch - Chemical compatibility check: find out which materials are compatible with the media used in your application. - Integration of Trelleborg Sealing Solutions Videos
MechTab
This app offers a comprehensive set of tools for mechanics, providing essential data on tolerances, threads, cutting speeds, wrench sizes, and roughness. It also includes calculators for material weight, triangle properties, and trowalisation.
- ISO-Tolerance data (holes and shafts)
- Thread specifications
- Cutting data calculations
- Wrench size conversions
- Roughness parameters
- Material weight calculator
- Triangle property calculator
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Werder AG introduces the ultimate tool for mechanics. MechTab provides information about ISO-Tolerances, Threads, Cutting Data, Wrench Size and Roughness. Tolerances: A - ZC, holes and shafts General Tolerances: Charts for linear dimensions, radii/chamfer and angular dimensions. Geometrical Tolerances: Symbols, drawings and explanations as well as charts for the different geometrical tolerances. Threads: BA, BSF, G, Heli-Coil, M, MF, Pg, Tr, UNC, UNEF, UNF, W, Metric-Non-Standard Cutting Data: Cutting Speed and Spindle Speed, Feed Rates, Processing duration Wrench-Size to Width across Corners: 4-,6-8-,10-,12-,14-Cornered Torque: 3.6, 6.9, 8.8, 10.9, 12.9 Roughness: Rz, Ra, N, Triangle-Notation Weight: calculate the weight of different materials in different profiles. Material list is editable. Triangle: calculate sides, angles and the area of a triangle by entering 3 values according to a drawing. Trowalisation: calculate the number of pieces
Screenshots
Verdict
The clearest difference is rating: MechTab at 4.1 against O's 3.8. MechTab also leads on ratings volume (16 vs 5). O's advantage is update cadence (every 3 months vs every 9 months) and iOS requirement (12.1 vs 15.0). On price, review sentiment, ads 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.
MechTab holds the better App Store score, 4.1 against 3.8. Both are backed by a comparable volume of ratings — 5 and 16 respectively. Written reviews point the same way: 83% of O's written reviews are positive against 89% of MechTab's.
O ships an update every 3 months, MechTab every 9 months. The most recent releases landed on June 4, 2026 and September 15, 2026 respectively.
| Parameter | O | MechTab |
|---|---|---|
| Price | Free | Free |
| Rating | 3.8 (5 ratings) | 4.1 (16 ratings) — better |
| Positive reviews | 83.3% of reviews | 88.6% of reviews — better |
| Number of ratings | 5 | 16 — better |
| Update frequency | Every 3 months — better | Every 9 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 12.1 — better | 15.0 |
| Further details — not scored | ||
| Size | 26 MB | 9 MB |
| Age rating | 12+ | 4+ |
| Developer | Trelleborg Sealing Solutions | Werder AG |
Customer experience
O
MechTab
In-app purchases
O
No in-app purchases
MechTab
No in-app purchases
Questions
Is O free?
Is MechTab free?
Which has better reviews, O or MechTab?
Do O or MechTab have ads?
Which is updated more often, O or MechTab?
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