Your battery's health is now read straight from your Tesla's own computer. Not an estimate any more: a measurement, sent even while the car sits parked.
Finally know the real condition of your Tesla's battery.
Not the charge percentage. Not a figure inferred from displayed range. State of Health — how much capacity your pack has left compared to the day it left the factory.
T4U is built by MyBatteryHealth, Europe's reference network for electric vehicle battery diagnostics. Over 70,000 batteries certified.
MEASURED, NOT ESTIMATED
Your car continuously reports the energy actually left in its pack. T4U reads that figure and derives your battery health from it. The vehicle's own computer does the measuring; we only translate.
This works with the car parked and locked. You get a fresh reading every day without anything ever disturbing your vehicle.
WHAT YOU GET
- State of Health as a percentage, with an MBH grade from A to E
- Current pack capacity in kWh, against its original capacity
- Real-world range, calculated from your own data
- Twelve-month degradation curve
- Manufacturer warranty tracking: years, mileage, minimum State of Health
- Battery chemistry, cell supplier, recommended charge limits
- Maximum charging power and Supercharger compatibility
- Live charge level, range and lock status
- Home screen widget, current even while the car sleeps
ADVANCED PACK DIAGNOSTICS
Where a consumer app stops at a percentage, T4U goes down to cell level:
- Voltage spread between the highest and lowest brick groups — the indicator that degrades before you lose any range
- Thermal spread between modules, and the position of the hottest sensor
- Internal pack resistance, measured while driving
- Open-circuit voltage, and voltage per cell
- Real cycle count, derived from lifetime energy consumed
Each of these identifies a weak point by its number inside the pack. That is what lets you document a fault with a professional.
YOUR BATTERY CARD
Generate your score and share it. A social-ready card carrying your grade, your battery health, your mileage and the MyBatteryHealth certification.
THE OFFICIAL MBH REPORT
Issue a digitally signed battery health certificate, verifiable by QR code. A document recognised by automotive professionals, leasing companies and used car buyers — and the strongest argument you have when defending your Tesla's price at resale.
WHAT T4U DOES NOT DO
T4U has no permission to command your vehicle, and never asks for one. It will not wake it, unlock it or move it.
No location data is collected. Distance is reconstructed from the odometer.
Every figure on screen states where it came from and when it was measured. A number you cannot explain is worth nothing.
T4U PREMIUM
The subscription unlocks full cell-level diagnostics, weak point localisation inside the pack, twelve months of history, driving performance and unlimited sharing of your battery card.
€1.99 per month or €14.99 per year.
Terms of use: https://tesla-4u.com/en/privacy-legal/
Privacy policy: https://tesla-4u.com/en/rgpd/
T4U is an independent app published by VIA SAS. It is not affiliated with, endorsed by or sponsored by Tesla, Inc. Tesla, Model S, Model 3, Model X and Model Y are trademarks of Tesla, Inc.
I was using this app on my M3 along with another iOS app Stats for Tesla. I’ve been using both apps about a month now and have been consistently losing about 20 miles of range each 24 hour period. I did an experiment whereby I changed my main Tesla password and reloaded each app individually. I discovered that Stats for Tesla did not contribute to vampire drain whatsoever. However, this app Tesla 4 U contributed significantly to vampire drain at the rate of anywhere from .66 to 1.2 miles per hour which is unacceptable. By the way, without this app polling my car I lost no range after 11 hours. Although this app has some nice features and it’s free, I can’t recommend due to the high vampire drain rates.
Developer Response
Try our new version with scheduled request. There is NO vampire drain
Just doesn't work..
meites
Literally you cannot get information at allOnce you login it will log you out once a day and and tell you the token is invalid there's nowhere to really refresh the token which I'm not sure why any application you refresh a token every single day. (they're actually actually is no place to do that)All I can tell is don't waste your money.. this is a horrific execution of an application..
Very handy
emorog
I wanted two main things from this app and it delivered. Charging status and logs and driving efficiency logs. These both work very well!On peculiarity is that the "parked" event updated every 1.5 hours or so during the night. I'm not sure if it was caused by GPS drift, or something else waking it up and registering a new "parked" event. I haven't tested long enough to see if it contributes to vampire drain or not. But I don't see any controls for polling frequency as was suggested by the dev response to another review.Update: I just found the charts for driving and charging! So very cool!This was not immediately obvious so, Open an event, like driving. It will show a map. (cool, right?) Now expand the arrow at the bottom of the screen to see the details. Then swipe L/R to see the charts!
The app we’ve long waited for!!
Philkun
Finally an app that tracks (and logs !) all stats such as speed, battery consumption, trip maps, etc. accurately. Kudos! Keep the updates coming. I’d definitely be willing to pay for this, too.
YOUR BATTERY HEALTH FOR REAL
8.9.3 : Update for Model Y SR
Your Tesla now continuously reports the energy actually left in its pack. T4U reads that figure straight from the vehicle's computer, even while parked. No more deriving health from displayed range.
The direct consequence: one single figure everywhere — home, diagnostics, shareable card and widget. It stays on screen even with no connection.
PACK DIAGNOSTICS, CELL BY CELL
Voltage spread between brick groups, thermal spread between modules, internal resistance, open-circuit voltage, real cycle count. Every weak point is identified by its number inside the pack.
A WIDGET THAT NO LONGER GOES STALE
The widget updates while the car sleeps and while the app stays closed for days. Charge, range and health, current on your home screen.
REDESIGNED HOME SCREEN
Every pack reading now sits in one place. High voltage safety no longer takes up room while everything is fine — and becomes impossible to miss if anything is wrong.
DRIVING EFFICIENCY
Now based on your own car's range estimate compared with its rated range. One value per day, steadier and fairer.
ALSO IMPROVED
- Far more reliable connection to your Tesla account: no more unexplained sign-outs
- Hardened access to your diagnostic data
- Every reading now states how it was obtained, and when
- Displayed range corrected, now matching your car's own screen
- Numerous display fixes
Thank you for the feedback — keep it coming, it genuinely shapes what we work on.
Version 9.0
The developer, VIA - Vehicle Information application, 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.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
VIA
Size
3.3 MB
Category
Utilities
Compatibility
Requires iOS 17.7 or later.
iPhone Requires iOS 17.7 or later.
iPad Requires iPadOS 17.7 or later.
Mac Requires macOS 14.7 or later and a Mac with Apple M1 chip or later.
