GWP vs Physics Questions
Price, ratings, monetisation and update history for both apps, side by side β with what reviewers say about each.
GWP
This tool helps convert between metric tonnes, ODP tonnes, and CO2-equivalent tonnes for substances controlled by the Montreal Protocol. It features two modes: 'Actual Values' and 'Kigali Amendment', and supports English, French, and Spanish.
- Converts metric tonnes, ODP tonnes, and CO2-equivalent tonnes
- Includes Kigali Amendment mode
- Supports 'Actual Values' and 'Kigali Amendment' modes
- Displays substance ODP, GWP, and description
- Calculates for single component substances and refrigerant mixtures
- Available in English, French, and Spanish
Read full descriptionHide full description
The UNEP OzonAction GWP-ODP Calculator app will help you to convert between values in metric tonnes, ODP tonnes and CO2-equivalent tonnes (or kg) of substances controlled by the Montreal Protocol and their alternatives. The updated application now includes a new Kigali Amendment mode. The app can now be used in two different modes: the regular "Actual Values" mode and the "Kigali Amendment" mode. In the Kigali Amendment mode, the global warming potential (GWP) values provided are those specified in the Kigali Amendment to the Montreal Protocol, i.e. GWP values are only assigned to controlled HFCs. In this mode the GWP values used to calculate the refrigerant blends/mixtures only include GWP contributions from components that are controlled HFCs. The user can effortlessly switch between modes. The OzonAction GWP-ODP Calculator uses standard ODP values and GWP values as specified in the text of the Montreal Protocol to make the conversions; other ozone depleting potential and global warming potential values from the recent reports from the Montreal Protocol technology and scientific expert panels as well as the Intergovernmental Panel on Climate Change (IPCC) are used when appropriate, with references to sources of all values used. The app includes new refrigerant mixtures (with ASHRAE approved refrigerant designations). The app can be viewed in English, French or Spanish. For single component substances simply select a substance from the dropdown list and enter the known value in the appropriate field (e.g. a quantity in Metric tonnes). The calculator will automatically perform the conversion between metric tonnes, ODP tonnes and/or CO2-equivalent tonnes (or kg) and display the corresponding converted values. The ODP, GWP and description of substance are also provided. For refrigerant mixtures/blends, simply select the name of the blend and enter the quantity. The calculator will display the corresponding total ODP tonnes and CO2- equivalent tonnes for that quantity of substance. The components of the mixture and their relative proportions (metric, ODP, CO2- equivalent) are also displayed. Both these types of calculations can be carried out in both the "Actual Values" mode and the "Kigali Amendment" mode. This application is designed primarily for use by Montreal Protocol National Ozone Units and other related stakeholders. The application was produced by UN Environment Programme (UNEP) OzonAction as a tool principally for developing countries to assist them in meeting their reporting and other commitments under the Protocol and is part of the OzonAction work programme under the Multilateral Fund for the Implementation of the Montreal Protocol.
Physics Questions
Read full descriptionHide full description
Best tool for school or college for practising all those physics questions! This app will help you to learn about the different concepts in physics. With separate modules for each subject area, you can practice: ---> Electricity ---> Electronics ---> Electromagnetism ---> Force & Energy ---> Motion ---> Optics ---> Radioactivity & Thermodynamics ---> Special Relativity ---> Waves & Particles At the press of a button, you can be prompted with the correct formula as well as being shown the worked solution. Want a feature to be added? Let me know at apps@sionnagh.com
Screenshots
Verdict
The clearest difference is in-app purchases: GWP at none against Physics Questions's 9. GWP also leads on ads (none vs shown). Physics Questions's advantage is update cadence (every 4 days vs every 38 months). On price, device support and iOS requirement there is nothing between them.
Scored on Price Β· Rating Β· Positive reviews Β· Number of ratings Β· Update frequency Β· Ads Β· In-app purchases Β· Monetization Β· Best chart rank Β· Devices Β· Requires iOS
Both are free to download. Physics Questions sells 9 one-off in-app purchases. GWP asks for nothing beyond the download.
GWP ships an update every 38 months, Physics Questions every 4 days. The most recent releases landed on October 23, 2026 and October 6, 2026 respectively.
| Parameter | GWP | Physics Questions |
|---|---|---|
| Price | Free | Free |
| Positive reviews | 100.0% of reviews | β |
| Update frequency | Every 38 months | Every 4 days β better |
| Ads | No β better | Yes |
| In-app purchases | No β better | Yes |
| Monetization | Free | β |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 11.0 β better | 12.0 |
| Further details β not scored | ||
| Size | 28 MB | 20 MB |
| Age rating | 17+ | 4+ |
| Developer | UNEP | Michael Todd |
In-app purchases
GWP
No in-app purchases
Physics Questions
- Electricity Questions$1.99
- Electronics Questions$1.99
- Electromagnetism Questions$1.99
Show 6 moreShow fewer
- Force & Energy Questions$1.99
- Motion Questions$1.99
- Optics Questions$1.99
- Radioactivity & Thermodynamics$1.99
- Special Relativity Questions$1.99
- Waves & Particles Questions$1.99
Questions
Is GWP free?
Is Physics Questions free?
Do GWP or Physics Questions have ads?
Which is updated more often, GWP or Physics Questions?
Other comparisons















