Comparison

O2 Duration vs Unit Converter For Medics

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

Head to head
About

O2 Duration

Calculate the approximate remaining oxygen in portable cylinders. Select your tank size, input current pressure and desired flow rate to see duration in minutes. Features a timer with alerts for low pressure.

Highlights
  • Oxygen cylinder duration calculation
  • Supports multiple cylinder sizes (A, B, D, E, G, H, K, M)
  • Input current tank pressure
  • Input desired flow rate
  • Displays duration in minutes
  • Running timer with remaining time
  • Low pressure alerts (500lbs and 0lbs)
Features
Read full description

O2 Duration is an oxygen consumption calculator for various oxygen cylinder sizes. This is the easiest way to quickly determine the approximate number of minutes until an oxygen tank will be depleted of oxygen. This tool is a must have for Nurse's and EMT’s who work with portable oxygen cylinders. The application allows you to select cylinder tank sizes A, B, D E, G, H, K and M. With the current tank pressure and desired flow rate, the app will display the oxygen duration in minutes. Additionally, a timer can be started which will display a running tank pressure and time in minutes remaining until the tank is empty. When tank pressure reaches 500lbs or when the tank pressure is zero the application will alert you. This is not a substitute for looking at the oxygen cylinder gauge to determine actual pressure and should not be relied on as a means to determine oxygen remaining.

About

Unit Converter For Medics

Features
Read full description

Conversion units from imperial to metric and vice versa is always a nuisance. Juggling multiple sources to do easy and repetitive tasks on daily basis is a torture. This App solves this problem. It converts 4 basic and essential values that we come across surprisingly often. Weight - kg / st / lb Height - cm / ft / in Temperature - °C / °K / °F Blood Glucose - mmol/L / mg/dL Quick and easy, does what it says on the tin. Just enter the value you wish to convert.

Screenshots

O2 Duration3 screens
Unit Converter For Medics4 screens

Verdict

The call

The clearest difference is price: Unit Converter For Medics at Free against O2 Duration's $2.99. Unit Converter For Medics also leads on update cadence (every 7 months vs every 15 months). O2 Duration's advantage is iOS requirement (7.0 vs 12.1). On 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

Unit Converter For Medics is free to download; O2 Duration costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

O2 Duration ships an update every 15 months, Unit Converter For Medics every 7 months. The most recent releases landed on October 15, 2026 and October 25, 2026 respectively.

Scorecard3 real differences · 7 level
O2 Duration versus Unit Converter For Medics: the parameters behind the verdict, then further details
ParameterO2 DurationUnit Converter For Medics
Price$2.99Free — better
Rating1.0 (1 ratings) — better—
Positive reviews0.0% of reviews—
Number of ratings1 — better—
Update frequencyEvery 15 monthsEvery 7 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhone, iPodiPhone, iPad, iPod — better
Requires iOS7.0 — better12.1
Further details — not scored
Size1 MB14 MB
Age rating4+4+
DeveloperAdvanced Aviation LLCKrzysztof Gwiazda

In-app purchases

None

O2 Duration

No in-app purchases

None

Unit Converter For Medics

No in-app purchases

Questions

Is O2 Duration free?
O2 Duration costs $2.99, with no in-app purchases.
Is Unit Converter For Medics free?
Unit Converter For Medics is free to download, with no in-app purchases.
Do O2 Duration or Unit Converter For Medics have ads?
Neither O2 Duration nor Unit Converter For Medics shows ads.
Which is updated more often, O2 Duration or Unit Converter For Medics?
O2 Duration ships an update every 15 months, and Unit Converter For Medics every 7 months. Most recently, O2 Duration was updated on October 15, 2026 and Unit Converter For Medics on October 25, 2026.

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