Singular vs RefMind

Singular is a professional-grade analog & logic circuit simulator designed for your iPhone and iPad. Build, simulate, and analyze electronic circuits with an intuitive drag-and-drop editor and a powerful real-time simulation engine — no internet required. Whether you're an electrical engineering student studying for exams, a maker prototyping your next project, or a professional verifying a design, Singular gives you a complete electronics workbench in your pocket. POWERFUL SIMULATION ENGINE • Modified Nodal Analysis (MNA) with TR-BDF2 adaptive solver • Real-time transient, DC, and AC analysis • Frequency-aware adaptive timestep — accurate results at any speed • Newton-Raphson nonlinear convergence for semiconductors • Hot-swap: modify your circuit while simulation is running 40+ ELECTRONIC COMPONENTS Passive — Resistor, Capacitor, Inductor, Potentiometer Sources — DC Voltage, AC Voltage, Pulse Generator Diodes — Standard Diode, Ideal Diode, LED Transistors — NPN, PNP, Darlington PNP, N-MOSFET, P-MOSFET Integrated Circuits — NE555 Timer, Operational Amplifier (Op-Amp) Logic Gates — AND, OR, NAND, NOR, XOR, XNOR, Inverter, Buffer Flip-Flops — D, JK, T Flip-Flop, SR Latch Measurement — Voltmeter, Ammeter Power Rails — Ground, VCC, VDD, VSS, VEE, ±3.3V, ±5V REAL-TIME OSCILLOSCOPE • Multi-trace display with color-coded signals • Adjustable time base and voltage scale • Pinch-to-zoom and pan gestures • 60 fps rendering — smooth and responsive INTUITIVE CIRCUIT EDITOR • Drag-and-drop component placement with grid snapping • Draw wires by tapping terminals — automatic routing • Rotate, flip, and mirror components freely • Multi-select, move, and organize your design • Full undo/redo history (up to 100 steps) • Pinch zoom (0.1x–5x) and two-finger pan PROFESSIONAL TOOLS • Design Explorer with automatic reference designators (R1, C2, U3…) • Standard value picker — E12, E24, E96 resistor series and standard capacitor values • Built-in expression evaluator — type "10k*2.2" and get the result instantly • Real-time voltage, current, and power readouts on every component • Net name visualization for complex designs LEARN & EXPLORE • Built-in example circuits: Voltage Divider, Current Divider, Inverting Amplifier, 555 Timer Demo • Resource Center with reference articles • Detailed simulation error guide — understand what went wrong and why • Save examples to your workspace and modify them freely SAVE, EXPORT & SHARE • Save unlimited circuits to your workspace • Export circuits as portable .circuit files with embedded thumbnails • Import circuits from other users or devices • Add names, descriptions, and metadata to every project DESIGNED FOR iPAD & iPHONE • Built 100% with SwiftUI for a native Apple experience • Optimized for both touch and Apple Pencil • Works entirely offline — your data stays on your device Singular is the circuit simulator that students wish they had during lectures, that makers reach for at the workbench, and that engineers trust for quick verification. Download it and start building. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Refmind is a next-generation academic document management app designed for students, researchers, and educators. Powered by artificial intelligence, Refmind helps you not just store, but truly understand and leverage the content within scientific papers, theses, and academic materials. Key Features: + Chat with Your Documents — Ask questions directly to any PDF in your library and receive accurate, source-grounded answers. Refmind uses RAG (Retrieval-Augmented Generation) technology to ensure every response is backed by your actual documents. + Smart Summarization — Automatically distill lengthy papers into concise key points, saving hours of reading time. + Multi-Source Import — Add papers via DOI, URL, direct PDF upload, or sync from Google Drive, Dropbox, and OneDrive. Supports BibTeX and RIS formats for bulk import. + Knowledge Graph — Explore the network of connections between concepts, authors, and topics across your library through an interactive visual interface. + Compare Matrix — Compare multiple papers side by side across any research criteria, making literature synthesis faster than ever. + Fact Checking — Verify claims, statistics, and citations directly against trusted academic sources in your library. + Highlight & Annotate — Mark up and take notes directly on PDFs, all synced and fully searchable. + Multilingual Support — Full interface and AI responses in both Vietnamese and English. + Privacy-First — Firebase authentication, encrypted API key storage, and full control over your data. Refmind is ideal for students writing theses, researchers managing hundreds of papers, educators preparing course materials, and anyone who wants to get the most out of their academic reading.