Comparison

O vs FCM IoT

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

Head to head
About

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.

Highlights
  • 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
Features
Read full description

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

About

FCM IoT

Features
Read full description

eFMS is short of electronic facility management system, focus on company’s EHS, facility and admin management.This is a software with WEB dynamic template and workflow engine, provides customer one-stop SaaS on cloud platform, user can access it via H5, Webpage, APP. Free configuration of permissions, can be used on the same platform in multi-sites and factories, or can be deployed privately.

Screenshots

O4 screens
FCM IoT1 screens

Verdict

The call

The clearest difference is update cadence: FCM IoT at every 3 weeks against O's every 3 months. O's advantage is iOS requirement (12.1 vs 15.0). On price, ads, in-app purchases 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. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

O ships an update every 3 months, FCM IoT every 3 weeks. The most recent releases landed on October 23, 2026 and October 5, 2026 respectively.

Scorecard2 real differences · 8 level
O versus FCM IoT: the parameters behind the verdict, then further details
ParameterOFCM IoT
PriceFreeFree
Rating3.8 (5 ratings) — better—
Positive reviews83.3% of reviews—
Number of ratings5 — better—
Update frequencyEvery 3 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.1 — better15.0
Further details — not scored
Size26 MB96 MB
Age rating12+4+
DeveloperTrelleborg Sealing Solutions苏州曼捷科智能科技有限公司

In-app purchases

None

O

No in-app purchases

None

FCM IoT

No in-app purchases

Questions

Is O free?
O is free to download, with no in-app purchases.
Is FCM IoT free?
FCM IoT is free to download, with no in-app purchases.
Do O or FCM IoT have ads?
Neither O nor FCM IoT shows ads.
Which is updated more often, O or FCM IoT?
O ships an update every 3 months, and FCM IoT every 3 weeks. Most recently, O was updated on October 23, 2026 and FCM IoT on October 5, 2026.

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