Intervals by Staventabs vs Pansophia

Intervals by Staventabs – train your musical ear easily and effectively! Learn to recognize intervals by ear, improve your relative and perfect pitch, and develop your sense of harmony. The app is suitable for both beginners and advanced musicians. App Features: 1. Varied exercises: contrasting intervals, minor and major intervals, middle-range and wide intervals, mixed and advanced exercises. 2. Detailed information for each interval: see the interval on the staff, listen to it, and explore all its parameters. 3. Create your own exercises: choose intervals and customize tests to your preferences. 4. Premium features: full access to all exercises and intervals for custom practices. No subscriptions or recurring payments. 5. Suitable for all skill levels. Train your ear, improve your interval recognition and harmony skills – become a more professional musician with Intervals by Staventabs!

Pansophia is an offline STEM reference for engineers, scientists, and students — 25,400+ formulas, compounds, and reference tables across 18 disciplines including physics, chemistry, biology, mathematics, and every major field of engineering. No account. No ads. No tracking. No internet required. About a third of every discipline is free. WHY PANSOPHIA Every entry is curated, cross-referenced, and verified — not generated. When you need a decay constant, a beam capacity, or a CAS number, it has to be right, and it has to work without a signal. Built for the lab bench, the job site, and the exam desk. The kind of data you used to search for daily, or flip through a mountain of handbooks to find — now in one place. WHAT'S INSIDE - 3,000+ biological species with habitat, functions, structures, timeline - 1,200+ chemical compounds with properties, synthesis, hazards & CAS numbers - 700+ mechanical components — fasteners, bearings, hinges, latches, brackets, clamps, belts/chains, flanges, gears, couplings, pumps, pneumatics + hydraulics, etc - 500+ electronic components — transistors, op-amps, microcontrollers (Arduino/STM32/ESP32/RP2040), motors, sensors, LCDs, batteries, etc - 350+ chemistry lab reference entries — solvents, buffers (Tris/PBS/HEPES), catalysts (Pd, Grubbs, MacMillan), spectroscopy (NMR/IR/MS), HPLC/GC chromatography - 254 materials — alloys, polymers, ceramics, composites, AHSS, bulk metallic glasses, high-entropy alloys, fracture toughness & creep data - 231 astronomical objects — Messier catalog, notable stars, exoplanets, black holes - 280+ structural engineering tables — AISC W/HSS shapes & beam design, RC design, NDS wood design, foundations (spread/pile/mat/retaining), seismic design, soil classification, building codes, bridges - 80+ chemical engineering reference — distillation & absorption unit ops, TEMA heat exchangers, CSTR/PFR/PBR/fluidized reactors, ASME VIII pressure vessels, API 650/620 storage tanks, relief systems, ISA-5.1 P&ID symbols, NEC/ATEX hazardous areas, HAZOP/LOPA/SIL methodology - 220+ biomedical reference entries — FDA device classes, ASTM F-series implants, ISO 10993 biocompatibility, clinical trial phases, lab values (CBC/BMP/CMP/LFTs/ABG), vital signs by age, imaging (X-ray/CT/MRI/US/PET) - 280+ pharmacology drug classes — full WHO ATC coverage with mechanism, dosing, adverse effects, interactions - 111 nuclear isotopes with cross-sections and decay data - 72 named organic reactions with reagents, conditions & mechanisms - 61 algorithms with time/space complexity analysis - 56 statistical tests with assumptions, formulas & when to use each - 48 math identities — trig, integrals, Laplace & Fourier transform pairs 18 DISCIPLINES Physics, Chemistry, Biology, Mathematics, Computer Science, Artificial Intelligence, Statistics & Data Science, Electrical Engineering, Mechanical Engineering, Civil & Structural Engineering, Chemical Engineering, Biomedical Engineering, Industrial & Systems Engineering, Nuclear Engineering, Materials Science, Astronomy & Astrophysics, Earth & Environmental BUILT-IN TOOLS - Scientific Calculator — 52 built-in constants, trig/log/factorial, history - Unit Converter — 22 unit families including electrical & magnetic - Physical Constants — 163 constants with uncertainties, searchable & copyable - Quiz & Flashcards — SM-2 spaced repetition for coursework and exam prep CROSS-DISCIPLINE CONNECTIONS 27,500+ cross-references link related concepts across fields. Tap any reference to jump between disciplines — see how thermodynamics connects to chemical engineering, or how linear algebra powers machine learning. WORKS OFFLINE — ALL DATA BUNDLED All 25,400+ entries ship inside the app. Dark theme, native LaTeX equation rendering, and interactive 3D molecular models. PRICING About a third of every discipline is free — no account, no time limit. Unlock all 18 for $9.99, or one for $0.99. One-time purchase, no subscriptions.