Comparison

Drillstring Toolbox Premium vs Gas Compressibility Factor Z

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

Head to head
About

Drillstring Toolbox Premium

Features
Read full description

The DS-1 team has created this Drillstring Toolbox Premium! It's an advance calculator that does everything the free Drillstring toolbox does and more! With it you can find: - API-recommended makeup torques for drill-stem connections with whatever sizes you want to plug in. - The "T4" (maximum tensile capacity) torque for those connections, too. - Adjusted makeup torques when you want to optimize away from the standard numbers. - Tensile and torsion capacities for standard, thick-walled, and custom drill pipe tubes. - A combined load curve for whatever combination you come up with, which you can email to your colleagues. - Recommended makeup torques for many popular proprietary connections.

About

Gas Compressibility Factor Z

Features
Read full description

This app is a tool very useful for complex calculations of the gas compressibility factor Z for natural gases used in the Gas Law: PV = nRTZ. Formulas by Hall and Yarborough (1973) correlation to estimate z-factor of natural gas. Standing and Katz’s Chart to Z-Factor vs Reduced Pressure and Reduced Temperature was plotted by app using formulas by Hall and Yarborough (1973). Check for oil & gas applications in our portfolio on the App Store. Please visite our website for links at www.wellcontrol.com.br Please, you can contribute for improvements. Report bugs and suggestions to contact@wellcontrol.com.br DISCLAIMER: These tools & materials are provided 'as is' without warranties of any kind, express or implied. Please verify the tools provided by this application by yourself before you use them. Ensure you understand the impact of using these tools. Any use you choose to make of these tools & materials is undertaken by you entirely at you own risk.

Screenshots

Drillstring Toolbox Premium3 screens
Gas Compressibility Factor Z4 screens

Verdict

The call

The clearest difference is price: Gas Compressibility Factor Z at Free against Drillstring Toolbox Premium's $24.99. Gas Compressibility Factor Z also leads on update cadence (every 8 months vs every 24 months). On ads, in-app purchases, 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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

Gas Compressibility Factor Z is free to download; Drillstring Toolbox Premium costs $24.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Drillstring Toolbox Premium ships an update every 24 months, Gas Compressibility Factor Z every 8 months. The most recent releases landed on September 20, 2026 and October 7, 2026 respectively.

Scorecard2 real differences Β· 4 level
Drillstring Toolbox Premium versus Gas Compressibility Factor Z: the parameters behind the verdict, then further details
ParameterDrillstring Toolbox PremiumGas Compressibility Factor Z
Price$24.99Free β€” better
Update frequencyEvery 24 monthsEvery 8 months β€” better
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS14.013.0 β€” better
Further details β€” not scored
Size1 MB3 MB
Age rating4+4+
DeveloperBureau Veritas North America, Inc.Carlos Moura

In-app purchases

None

Drillstring Toolbox Premium

No in-app purchases

None

Gas Compressibility Factor Z

No in-app purchases

Questions

Is Drillstring Toolbox Premium free?
Drillstring Toolbox Premium costs $24.99, with no in-app purchases.
Is Gas Compressibility Factor Z free?
Gas Compressibility Factor Z is free to download, with no in-app purchases.
Do Drillstring Toolbox Premium or Gas Compressibility Factor Z have ads?
Neither Drillstring Toolbox Premium nor Gas Compressibility Factor Z shows ads.
Which is updated more often, Drillstring Toolbox Premium or Gas Compressibility Factor Z?
Drillstring Toolbox Premium ships an update every 24 months, and Gas Compressibility Factor Z every 8 months. Most recently, Drillstring Toolbox Premium was updated on September 20, 2026 and Gas Compressibility Factor Z on October 7, 2026.

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