RangeLendger
Charge log
Every session, from plug-in to unplug, with the numbers that make cost comparisons honest.
- Start and end state of charge
- kWh added, price paid, idle fees
- Location, network and connector
In development Personal iOS journal · Not a Tesla product
A quiet ledger for the miles you actually drive.
RangeLendger keeps charging sessions, trips, efficiency and service history in one place on your phone. You write the entries. Nobody else gets a copy.
- No accounts
- No trackers
- Entries stay on device
- Nothing sold, ever
Design illustration of the journal layout. The iOS app is in private development — this is not a screenshot of a shipped build.
- Zero
- accounts to create. The app opens straight to your entries.
- On-device
- storage by default, in the app's own local database.
- No pixels
- on this website. No analytics, no ad SDKs, no CDN fonts.
- Yours
- to export or erase. Delete the app and the record goes with it.
What it records
Four logs that answer the questions an EV owner actually asks.
What did that road trip really cost? Is the pack behaving the same as last winter? When was the cabin filter changed? One journal, four kinds of entry, no screenshots from three other apps.
Trip log
Distance with the context that explains it, so a bad efficiency day has a reason attached.
- Route, distance and duration
- Temperature, weather and load
- Energy used and Wh per mile
Efficiency
Trends calculated from your own entries — not an estimate borrowed from someone else's fleet.
- Wh/mi by trip, week or month
- Cost per mile against real charge cost
- Season-over-season comparison
Service log
Maintenance that stays findable years later, instead of scattered across texts and receipts.
- Tires, 12V, cabin filter, brake fluid
- Dated notes beside the odometer
- Shop, cost and what was actually done
How it works
Write it down. Read the pattern. Keep the file.
No sync queue, no onboarding funnel, no dashboard you have to log into. The whole loop takes about twenty seconds per entry.
Log it
Finish a charge, park after a trip, or leave the service centre, then add the entry in a few taps. The app opens to a form, not a sign-in screen.
See the pattern
RangeLendger does the arithmetic: Wh per mile, cost per mile, kWh per session, and how this winter compares to the last one you logged.
Keep it
Entries live in the app's on-device store and travel with your normal encrypted device backup. Export a copy whenever you want one elsewhere.
Connect later
If an official manufacturer owner API is ever wired in, it is opt-in, authorised on the manufacturer's own sign-in screen, scoped by you, and revocable there at any time.
Trust
Privacy isn't a page. It's the spec.
A journal about where you drive, when you charge and what you spend is sensitive by definition. So the design starts from the assumption that the data never needs to leave your phone.
-
Entries live on your device There is no RangeLendger account and no server holding your log. The app is built around a local store.
-
This site loads nothing third-party No analytics, no ad pixels, no fonts or scripts from a CDN. Plain HTML, one stylesheet, a few lines of JavaScript.
-
Any vehicle connection is opt-in Authorised in the manufacturer's own sign-in screen, limited to scopes you approve, and revocable there whenever you like.
-
Not a Tesla product RangeLendger is an independent personal project, not affiliated with, endorsed by or sponsored by Tesla, Inc.
-
Not a remote-control app It cannot lock, unlock, precondition or drive anything. It writes rows in a journal you keep.
-
Not a data business No sale of personal or vehicle data, no advertising profiles, no public user directory to join.
FAQ
The short answers.
Is this made by Tesla?
No. RangeLendger is an independent personal project and is not affiliated with, endorsed by or sponsored by Tesla, Inc. Tesla, Model 3 and related marks belong to Tesla, Inc. and are used here only to describe the vehicle the journal was written for.
Can it control my car?
No. There is no remote command surface of any kind. RangeLendger cannot lock, unlock, precondition, honk, open a port or move a vehicle. It records entries you type in.
Where does my data live?
In the app's own on-device store on your iPhone, and in whatever encrypted device backup you already use. This website has no accounts, no database and no login, so there is nothing here to breach.
Can I get my data back out?
That is the point of a journal. The design goal is a plain, readable export you can open in a spreadsheet, so your history is never trapped in someone else's format — including this one.
What is the /oauth/callback page for?
It is the registered redirect target for a possible future authorisation-code sign-in with an official manufacturer owner API. Today it only reports whether an authorisation succeeded or failed. It stores nothing and holds no secrets — this is a static site with no backend.
Where can I download it?
Nowhere yet, and there is no waitlist or beta to sign up for. RangeLendger is in private development for one owner's car — a 2018 Model 3 Performance — and this site exists so the project has a real home, a real privacy policy and the developer endpoints a manufacturer review expects.
Built for one car, in the open.
No growth targets, no telemetry pipeline, no data room. Just a careful record of what a single EV costs to run, and a public paper trail describing exactly what the app does and does not do with it.