Lambert vs ResToolbox3

This app turns your iPhone into a geological compass, a tool for each geologist. It can be used to measure the direction of dip and the angle of dip of geological strata. The app shows the current device orientation in a realtime stereographic projection. The data can be previewed in projection diagrams (Wulff and Schmidt Net) and transferred to your computer. You can add text to the measurements and plot the measurement localities on a map.

ResToolbox3 is a petroleum engineering calculator built for engineers who need answers fast - on a rig floor, in a meeting, or on a plane. PVT analysis, nodal analysis, gas hydrate prediction, production forecasting, volumetric calculations, and well testing, all from your iPhone or iPad. FLUID PROPERTIES (PVT) - Gas PVT: Z-factor, viscosity, compressibility, pseudo-pressure, water content, and thermal properties via 5-component Peng-Robinson EOS. Handles CO2, H2S, N2, H2, and hydrocarbon mixtures including pure and high-concentration cases - Oil PVT: Bubble point, solution GOR, formation volume factor, viscosity, and compressibility using Valko-McCain and Velarde correlations. Three solve modes with scaling factors for GOR and viscosity - Brine & Rock: Soreide-Whitson mutual solubility with Spivey brine correlations. Gas composition from Gas PVT flows through automatically GAS HYDRATES - Hydrate formation prediction via Motiee and Towler-Mokhatab correlations - Thermodynamic inhibitor dosing for MEG, DEG, TEG, methanol, and ethanol - Interactive P-T stability curves with inhibited and uninhibited envelopes - Water content mass balance between reservoir and operating conditions NODAL ANALYSIS - Gas and oil well inflow performance (IPR) with non-Darcy flow and Vogel - Outflow performance (VLP) via four methods: Woldesemayat-Ghajar, Hagedorn-Brown, Beggs & Brill, and Gray - 3x3 sensitivity matrix or real-time Explorer mode with interactive sliders - Water cut modelling with physics-based two-phase flow - Injection well support PRODUCTION FORECASTING - Single-well decline profiles: hyperbolic, exponential, and harmonic - Two-stage decline with continuous slope matching - Multi-well field development with drilling schedule, plateau constraints, and abandonment rate VOLUMETRICS - Deterministic OGIP and OOIP with combined gas/oil mode - Monte Carlo probabilistic analysis with Normal, Log-Normal, and Triangular distributions - Exceedance probability curves with P90, P50, and P10 reporting WELL TEST & TOOLS - Choke flow: gas mode (Gilbert, Norsok, TAM, SLB) and oil mode (Gilbert, Ros, Baxendell, Achong) - AGA-3 orifice metering for gas and ISO 5167 for liquid - Gas flowline pressure drop: 30-segment Darcy-Weisbach with PR-EOS properties at each segment, plus Weymouth and Panhandle B empirical methods - Petrophysics: Archie equation with density, sonic, and direct porosity methods, Pickett plot - Gas heating value and composition - Pipe capacities database (tubing, casing, drill pipe) - Unit converter with HC equivalents, reciprocal GOR/CGR, and density-gradient conversions DESIGNED FOR THE FIELD - iPhone-first interface with iPad responsive layouts - Oilfield and Metric unit systems with one-tap toggle - Share results and charts via email or messaging - Available in English, Norwegian, French, Chinese, Spanish, and Arabic - Works fully offline - no internet connection required - PVT properties flow between modules automatically All calculations use published, peer-reviewed methods from SPE literature and industry-standard references. No proprietary correlations, no curve-fitted shortcuts. Tabular data exports let you paste results directly into Excel or Google Sheets.