Tyre Pressure by Temp

Tyre pressure falls as the air gets colder. Enter the pressure printed on your door placard once, along with the temperature it was set at, and this app estimates what your tyres would read at today's temperature — and roughly how much air it would take to get back to the placard figure. No sensors. No Bluetooth. Nothing to buy or fit. Every other tyre pressure app expects you to install hardware on your valves. This one is simply arithmetic done carefully, using the temperature outside your window. WHAT IT DOES • Estimates today's pressure from your placard setting and the current temperature • Shows the top-up estimate — how much to add to reach your target • Picks up the current temperature automatically from your local forecast • Warns you the night before a cold morning, so a hard frost isn't a surprise • Temperature slider to explore "what if it drops to -10°C?" • Home Screen widget shows the morning estimate without opening the app BUILT FOR EVERY VEHICLE YOU OWN Add as many as you like: car, motorbike, bicycle, campervan or trailer. Front and rear axles can carry different targets, and each vehicle keeps its own unit — because placards are printed in bar in one country and psi or kPa in the next. • bar, psi and kPa, switchable per vehicle • Separate front and rear targets • Your vehicles stay on your device THE MATHS, IN THE OPEN The estimate is the ideal gas law at constant volume. The step most rules of thumb skip is converting gauge pressure to absolute pressure before applying the ratio, then converting back. Skipping it overstates the change by roughly 40 per cent. This app does the conversion, and the settings screen shows you the formula so you can check the working yourself. PLEASE READ Every figure here is an estimate meant to help you decide when to visit the airline. It is not a measurement and not a replacement for one. • Your vehicle's door placard is the authority on target pressure • Check with a gauge before adjusting anything • Pressure readings only compare properly on cold tyres — parked three hours or more, before driving. Driving heats tyres and raises the reading • Your phone measures nothing; the app cannot see your actual tyres PRIVACY Your location is used only to look up the temperature nearby, rounded before it is sent, and never stored or shared. Your vehicles stay on your device. ONE PURCHASE Buy it once and everything is included. No subscription, no in-app purchases, no adverts.