OBD2 Scanner | OBD Auto Doctor vs OBD2 Logger

Turn your iPhone into a powerful OBD2 car scanner and diagnose your vehicle yourself. Check why your Check Engine Light is on, read and clear diagnostic trouble codes, monitor live engine data, and check emissions readiness — all from your iPhone or iPad with a compatible OBD2 dongle. CHECK YOUR CHECK ENGINE LIGHT Don't guess what's wrong with your car. OBD Auto Doctor reads diagnostic trouble codes from your vehicle and provides detailed information to help you understand what they mean. • Read diagnostic trouble codes (DTCs) • Clear Check Engine Light codes • View detailed code descriptions • Read freeze-frame data MONITOR YOUR CAR IN REAL TIME See what's happening while your engine is running with live OBD2 data. • Engine RPM and vehicle speed • Coolant temperature • Fuel system and fuel trim data • Throttle position • Intake air and engine load • Oxygen sensor data • And many other vehicle parameters Create your own dashboard and choose exactly which sensors you want to monitor. CHECK EMISSIONS READINESS Preparing for an emissions or vehicle inspection? Check your vehicle's readiness monitors and see whether your car's emissions systems have completed their tests. WORKS WITH OBD2 DONGLES Connect OBD Auto Doctor to your vehicle using a compatible Bluetooth, Wi-Fi or Bluetooth Low Energy (BLE) OBD2 dongle. Compatible dongles include many ELM327-based adapters, OBDLink, Vgate, Linker, Veepeak and other compatible OBD2 interfaces. Please note: An OBD2 dongle is required to connect the app to your vehicle. Dongle compatibility and available features depend on your vehicle. MORE THAN JUST A CODE READER OBD Auto Doctor gives you access to the information your car's onboard diagnostic system makes available. • Read vehicle information • Monitor fuel consumption • View and record live sensor data • Read diagnostic trouble codes • Clear diagnostic trouble codes • Check emissions readiness • View freeze-frame data • Monitor vehicle performance Whether you're trying to understand a Check Engine Light, preparing your car for inspection, monitoring your engine, or simply want to know more about your vehicle, OBD Auto Doctor puts professional-style OBD2 diagnostics in your pocket. Download OBD Auto Doctor and start diagnosing your car today. SUBSCRIPTION OBD Auto Doctor offers optional subscriptions that unlock additional features. Terms of Use: https://www.obdautodoctor.com/terms

OBD2 Logger turns your iPhone into a precision data logger for any modern car. Plug a Bluetooth ELM327 adapter into your vehicle's OBD2 port, pair it once, and stream live engine, hybrid, battery, and emissions data straight into per-session CSV files on your phone. No accounts. No cloud. No analytics. Your driving data never leaves your device. LIVE READOUT • 40+ standard SAE J1979 PIDs, automatically discovered from your car: RPM, vehicle speed, coolant temp, throttle, MAF, intake MAP, fuel trims, catalyst temperatures, and more. • Manufacturer-specific Mode 21 PIDs on profiled vehicles — including HV pack voltage, MG1/MG2 motor torque, and battery cell-block temperatures on Toyota/Lexus hybrids. • Values grouped by category (Engine, Hybrid, Battery, Emissions, Diagnostics) and updated every second. • One CSV per logging session, written into the app's Files container — open it in Numbers, Excel, pandas, DuckDB, or any other tool with no preprocessing. • Wide-table format: ISO-8601 timestamps, one column per active PID, blank cells where the ECU returned no data (no spurious forward-fill). • Smart-stop after extended idle so you don't end up with a tail of empty rows when you forget to tap Stop. WORKS IN THE BACKGROUND • Keeps logging while you drive with Maps in the foreground or the screen off, using Apple's standard background location mode for trip-tracking apps. The system location indicator is shown the entire time. We don't store your location. VEHICLE PROFILES • Ships with three profiles: a generic Mode-01 fallback, a Toyota hybrid family profile, and a 2020 Lexus RX 450h/450hL profile validated against a real vehicle. • VIN auto-read on connect; year, make, model, and trim pre-filled from NHTSA's free public vPIC API. • Import any third-party profile JSON to add coverage for your car. The format is documented and human-readable. DON'T HAVE AN ADAPTER YET? • Tap "Try demo mode" on the second onboarding step to explore the app end-to-end with synthetic data — no hardware required. WHAT YOU NEED • Any Bluetooth Low Energy ELM327 adapter (Veepeak OBDCheck BLE+, vLinker MC+, OBDLink, etc. — most BLE clones work). USB-only and Wi-Fi-only adapters are NOT supported. • A car with an OBD2 port (1996+ in the US, 2001+ in the EU). PRIVACY • Nothing is collected, transmitted, or stored on our servers — we don't have servers. The only outbound call the app ever makes is one VIN decode per vehicle to NHTSA's vPIC API. • Your CSVs and vehicle records live in the app's Files container, accessible to you in the iOS Files app under On My iPhone → OBD2 Logger. • Open source: github.com/NathanNam/obd2-logger