TachoSpeed is a standalone GPS tachometer and speedometer for vehicles whose speedometer doesn't work but whose tachometer does — classic cars, restorations, project cars, anything with a working dash tach but a stuck or missing speedo.

You calibrate once. Pick a cruising gear, settle at a steady speed, read the exact RPM off your dash tachometer, and tap to log. That single point is enough — because gear ratios are linear within a gear, TachoSpeed can derive your engine RPM from any future GPS speed.

From then on, you get a live analog tachometer dial with:

• An RPM scale around the outer ring with adjustable max and redline
• A matching road-speed scale on the inner ring, so a single needle reads both at once
• Current GPS speed shown as a large digital readout in the lower wedge of the dial

The RPM dial is accurate in the gear you calibrated. The digital GPS speed is accurate in any gear — including downshifts, neutral, and the moments between shifts.

No OBD-II adapter. No cables. No accounts. No ads. No tracking. TachoSpeed makes no network requests of any kind — your GPS speed is read from the phone's location services and processed entirely on-device. Nothing leaves your phone.

FEATURES

• Live analog tachometer dial driven by your phone's GPS
• One-time calibration in any gear of your choice; recalibrate any time
• Adjustable dial maximum from 4,000 to 12,000 RPM and adjustable redline
• MPH or KM/H, your choice — both scales update instantly
• Screen stays awake on the tachometer view
• Built-in safety notice — please don't operate the app while driving; mount your phone or have a passenger hold it

Built for classic-car owners, vintage motorcyclists (use it as a passenger), restoration shops, and anyone whose dash speedo reads zero but whose tachometer still works.

TachoSpeed is published by Skunk River Restorations, the same team behind LastDrive and Fuel Pre-Pay Estimator.