Baseline OBD
Your car's margins, each drive
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Reads your car's own diagnostic tests on every drive and watches how far each one sits from its limit. Read-only. Everything stays on your phone.
Baseline reads your car through a Bluetooth OBD-II adapter, keeps a record of every drive, and watches the margins on the car's own on-board tests, so a part that is wearing shows long before its warning light.
Every drive, kept. Plug in the adapter once. From then on Baseline connects on its own when the car wakes up, takes a snapshot (identification, codes, freeze frame, on-board monitor results) and records the drive, even with the phone in your pocket.
Margins, not just codes. A code is the cliff. Baseline shows the distance to it: the catalyst's own efficiency test, the oxygen sensor, fuel trim, warm-up rate, the 12 V battery at rest, and the engine's misfire counters per cylinder, polled every 30 seconds and timed against engine starts.
Evidence you can hand over. A pending code and its freeze frame vanish at the end of the next clean drive. Baseline keeps them and exports an evidence packet: a PDF, CSV files and the raw records, with the readings exactly as the car reported them.
Trend and crossing estimates, in beta. Once a test has enough drives, Baseline fits a line to your own car's readings and estimates when it would reach the limit. These estimates are labelled beta wherever they appear.
Private by design. No account, no server, no tracking. Everything stays on your iPhone unless you export it.
Works with
- Cars sold in the United States from model year 2008 on (CAN OBD-II), and many 2004–2007 cars.
- The OBDLink CX Bluetooth LE adapter. ELM327-based Bluetooth LE adapters (Vgate iCar Pro BLE, Veepeak OBDCheck BLE, vLinker BLE) should connect but are untested; Wi-Fi and classic Bluetooth adapters cannot be used by an iPhone app.
Baseline reads only. It never writes to the car and never clears a code. It is not a substitute for a professional diagnosis: when your car's own warning light is on, have it looked at.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
The developer, Alphonse Romero, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Alphonse Romero
- Size
- 3.5 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 A. Romero