Dr. DE vs Kyanite Pro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Dr. DE
This mobile toolbox simplifies complex drilling engineering calculations. It offers a comprehensive suite of 29 functions across 11 categories, eliminating the need for handbooks and improving efficiency for engineers and technicians.
- 29 drilling engineering functions
- 11 functional groups
- Bit hydraulics calculations
- Hole cleaning analysis
- Well control solutions
- Unit conversion tools
- Tank capacity calculations
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Do you want to solve drilling engineering problems in seconds? It is easier than ever before to use Dr. DE Lite mobile app, a must-have toolbox app that includes a substantial collection of functions for every drilling engineer and technician. Bid farewell to flipping through handbooks, textbooks, standards, etc. for answers. This free app, sophisticated yet simple to use, not only saves time and money, but also makes your engineering and sales efforts more reliable and professional. The Dr. DE Lite app is equipped with 29 functions that are divided into 11 groups. --Bit Hydraulics --Casing Centralizer --Hole Cleaning --Hydraulics --Mud Additives --Pipe --Pump --Tank Capacity --Volume and Capacity --Well Control --Unit Conversion
Kyanite Pro
This app offers a suite of offline drilling calculators and reference tools for oil and gas professionals. It includes features for mud engineers, cementers, and directional drillers, with options to share data with crews. A free tier provides basic tools, while a subscription unlocks advanced calculators and job sheets.
- Offline drilling calculators
- Mud, cement, and directional drilling tools
- Field notes and reference charts
- Crew data sharing
- Kill sheet and cement job sheet
- Chemical inventory management
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A professional calculation and reference tool for the people who run the well: drilling and mud engineers, solids control hands, cementers, directional drillers and MWD hands. The calculators work completely offline. No ads and no tracking, and no account is needed to use them. You only sign in to share records with your crew or use the web console. FREE TO START The scientific calculator, field notes, reference charts, volume tables and the hitch calendar are free, along with the full calculator catalog so you can see what you are paying for. KYANITE PRO Unlocks the 130+ field calculators, kill sheets, cement job sheets, gain/loss sheets, LCM build sheets, location volumes and chemical inventory. Start with a 7-day free trial, then $9.99 per month or $50 per year. It all works with no signal. KYANITE ULTRA Everything in Pro, plus DrillIQ and MudIQ, AI assistants for drilling engineering and drilling fluids that use your active well's figures, the Live Rig dashboard and the web console at app.kyanitepro.com. $20 per month or $119.99 per year. SHARE WITH YOUR CREW Keep one set of figures in front of everybody on location. Share tank gauge readings, chemical inventory, notes, LCM build sheets, kill sheets and cement jobs with the hands you work with, and every phone stays in step. Anything entered with no signal goes up when you have coverage, and your records stay private until you choose to share them. 130+ CALCULATORS Drilling engineering: capacities, volumes, string displacement, pump output and strokes, circulation times, hydrostatic, gradient, EMW, ECD, MAASP, lag time and ROP. Drilling fluids: mud weight conversions, oil/water ratio, weighted mixing, barite and hematite addition, dilution, PV, YP, gel strength, API fluid loss, retort solids and alkalinity. Solids control: solids percentage, low and high gravity solids, dilution and discard volume, screen mesh, centrifuge and hydrocyclone. Cementing: slurry yield and density, mix water, additives by percent BWOC, sacks, annular volume with hole excess, top of cement, balanced plug, displacement and strokes. Directional and MWD: minimum curvature, dogleg severity, interpolation, closure and vertical section, build and tangent sections, projections ahead, slide footage and toolface. Well control: formation pressure from SIDPP, kill mud weight, initial and final circulating pressure, the step-down schedule, maximum allowable mud weight from a leak-off test, MAASP, influx height and gas expansion. KILL SHEET A full IADC-style vertical well kill sheet you fill in before you need it. Keep the pre-recorded half current on a quiet tour; if the well is shut in, enter SIDPP, SICP and pit gain and the sheet works the kill with a full step-down schedule. CEMENT JOB SHEET Lay out a primary job end to end: capacities, barrels, sacks and mix water, the annulus drawn to scale and a pump schedule. Casing presets from 20 to 4-1/2 inch. LCM BUILD SHEET Design a lost circulation pill from your own inventory: pounds, sacks, concentration and cost per barrel, with a stock check. CHEMICAL INVENTORY A daily ledger of received, used, transferred and adjusted stock for every product. Old days are never overwritten. BUILT FOR THE FIELD Large touch targets and big results, readable in gloves and in the sun. ENGINEERING INTEGRITY Every calculator shows its equation, units, assumptions and a verification status: VERIFIED, NEEDS VERIFICATION or EQUIPMENT SPECIFIC. IMPORTANT Kyanite Engineering is a calculation and reference aid, not a well control program and not a substitute for engineering judgement. All results must be verified by qualified personnel. Well control decisions must follow the operator's and contractor's program and the person in charge on location. Subscriptions renew automatically unless cancelled at least 24 hours before the period ends. Terms: https://support.kyanitepro.com/terms.html Privacy: https://support.kyanitepro.com/privacy.html
Screenshots
Verdict
The clearest difference is rating: Kyanite Pro at 5.0 against Dr. DE's 4.5. Kyanite Pro also leads on update cadence (every 8 days vs every 3 months). Dr. DE's advantage is in-app purchases (none vs 7) and ratings volume (15 vs 2). On price, ads 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
Both are free to download. Kyanite Pro sells 7 in-app purchases, starting at $9.99 per month. Dr. DE asks for nothing beyond the download.
Kyanite Pro holds the better App Store score, 5.0 against 4.5. That said, the two scores are not equally well evidenced: Dr. DE has 15 ratings behind it against 2, so its average is the more settled of the two.
Dr. DE ships an update every 3 months, Kyanite Pro every 8 days. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.
| Parameter | Dr. DE | Kyanite Pro |
|---|---|---|
| Price | Free | Free |
| Rating | 4.5 (15 ratings) | 5.0 (2 ratings) — better |
| Positive reviews | 55.6% of reviews | — |
| Number of ratings | 15 — better | 2 |
| Update frequency | Every 3 months | Every 8 days — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free — better | Freemium |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 15.6 — better | 18.0 |
| Further details — not scored | ||
| Size | 33 MB | 30 MB |
| Age rating | 17+ | 4+ |
| Developer | Pegasus Vertex, Inc. | Mike Haynes |
Customer experience
Dr. DE
Kyanite Pro
In-app purchases
Dr. DE
No in-app purchases
Kyanite Pro
- Kyanite Pro Monthly7 Days trial$9.991 Month
- Kyanite Ultra Monthly$20.001 Month
- Kyanite Pro Yearly7 Days trial$50.001 Year
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- Kyanite Ultra Yearly$119.991 Year
- Starter Pack$2.99
- Value Pack$4.99
- Professional Pack$9.99








