If you want an abundance of numbers to obsess over when owning a Tesla, you’ll need more than just the app that comes with the car. Which third-party app is worth keeping on your phone? I downloaded the two most popular choices, TezLab and Tessie, and spent a few weeks with premium subscriptions to both to find out.

Things I like about TezLab

I spent a couple days using just TezLab first. The app impressed me early on with a ton of information, a lot of it I’d never have considered calculating, like the carbon intensity of charging based on my area’s energy sources.

Other metrics require a large population of users I’d never have access to otherwise, and TezLab has done a great job of leveraging their large user base to provide interesting features. TezLab allows users to rate Superchargers based on thoughtful dimensions, like access to quality bathrooms nearby, food in the area, or quality outdoor space to hang out in while charging. Through TezLab, I’m able to compare my own driving efficiency to other people driving the same model locally.

TezLab has cleverly gamified a lot of the quirky aspects of EV ownership. I unlocked badges by driving over 200 miles in a day, saving a bunch of money on fuel, updating firmware, and for receiving the highest charge rate at a Supercharger that week (that one’s impressive, Northgate is a busy charger). Leaderboards rank users on a bunch of metrics, like furthest driven between charges, highest odometer, and longest travel day, ranked both globally and among the users I follow.

Each charge location is tracked seperately, allowing me to specify the charge cost for extremely granular expense tracking. I can use TezLab’s community and my own charging history to find the best, most convenient, and lowest-cost chargers in an area whenever I need one.

Things I like about Tessie

After getting used to TezLab, I spent a few days with Tessie. I found that Tessie tracked a lot of the same information as TezLab, but added two of my favorite things: graphs and maps.

Tessie is all business. Gone are the gamification and social features TezLab provides, and in its place are fascinating visualizations and a much simpler user interface. The app’s minimal home view presents the state of the car up top, a few configurable controls, then six buttons leading to more detailed information.

Drilling down to the Charging view, I’m presented with a timeline of all my charge sessions. I can edit the charger name and cost here, allowing for granular cost tracking, similar to TezLab. In the Analytics tab, I can track the energy usage, charging efficiency, cost, and relative fuel cost over a configurable period of time.

Tessie will estimate maximum usable battery capacity from any charge that adds at least 10%, meaning frequest calculations and more data points tracking battery degradation over time. Tessie’s maps allow me to track everywhere I’ve driven, parked, and charged over any time period — a killer feature for a guy like me who wants to map everything.

A well-considered Apple Watch app rounds out Tessie’s offering. The app provides a battery complication for my watch face, so I don’t even need to open my phone to check the battery. Tapping the battery value brings me to the full Apple Watch app, allowing me to pop the frunk, unlock the doors, and use the climate controls all from my wrist.

Things I dislike about TezLab

The first thing I noticed about TezLab was a cluttered and busy home view in the app itself. While TezLab tracked a ton of interesting information, a huge amount of prominent screen real estate is devoted to things that I don’t find that appealing, namely the social and gamification features. TezLab also tracks my carbon neutrality based on my energy usage and my area’s power generation sources and offers to have trees planted to offset carbon emissions at a cost. I’m sure some people appreciate this, but I found it trite and abstract: pay an app to cleanse my conscious of the guilt of my carbon emissions and hope trees eventually do actually get planted somewhere.

TezLab lacks a lot of the interesting visualization features that Tessie excels at, providing very few and fairly clunky graphs and maps. While notifications are configurable, I found the default overwhelming. Push notifications every time I start a drive, end a drive, efficiency reports, charge reports, badge unlocks, and more means I was clearing more TezLab notifications from my lock screen than anything else.

Like Tessie, TezLab will calculate battery health after a charge, but requires a much larger charge to do so, from 60% to 90%. I charge at Level 1 at home and set my charge limit to 80%, so a 60% to 90% charge could really only naturally happen during a rare long road trip. I have a feeling the calculation is probably more accurate user TezLab’s larger charge threshold, but I prefer the less accurate, more frequent snapshots.

Finally, TezLab’s Apple Watch offering is bad and only barely exists, as if to check a feature box. The UI elements are sized poorly for the watch screen and it offers no watch face complications, like Tessie’s state of charge.

Things I dislike about Tessie

While Tessie offers a crisper, more minimal user interface, it’s great weakness is the app is organized. I find the layout confusing, and can only quickly find information now because I remember where it is, not because its placement makes any sense.

For example, information on the battery is scattered across three different views: Battery, Charging, and Activity. Under Battery, you’ll find a detailed state of charge as well as an unlabeled, poorly scaled, unconfigurable graph showing the battery’s charge over time. Despite a lot of unused screen real estate in this view, battery health is another button press away. Under Charging, you’ll find charts showing the amount of energy added, used, cost of electricty, and proportional cost of fuel. Under Activity, you’ll find charts showing the battery’s charge (repeated, but this time as a much better chart), usable charge, range estimate, as well as charging power, current, and voltage. These are all broadly in the same category: the current state, charging history, and health of the battery, and they could reasonably be organized in the same view.

Similar to the Battery view, the Climate view wastes most of its screen real estate. A set of icons clustered in near the bottom are cleverly arranged to signal the position of the heater they control and center the steering wheel to apply both to left- and right-hand drive vehicles. The space above the heater icons is wasted. Aside from a large current interior temperature at the top, it’s blank.

My decision

I decided to renew my subscription to Tessie and delete TezLab. Both apps require a subscription to unlock all their features, and they’re similarly priced. Both offer yearly subscriptions for $49.99, but if you’re paying monthly, Tessie is priced at $4.99 and TezLab at $5.99. These prices were close enough that their small difference wasn’t an influence.

Ultimately, I after spending a few days using each app exclusively, I found myself reaching for Tessie most often. I found Tessie’s presentation to better suit what I was more interested in about my car, things like charging rates, mapping, charting, and price tracking, were easier through Tessie. I didn’t expect to be swayed by an Apple Watch app, but being able to check in on and control my car remotely without even unlocking my phone is great.

If I had a bunch of Tesla-owning friends, I’d probably be much more interested in TezLab’s social features. I appreciated that they placed my metrics in context ranked against drivers near me, but I’m mostly interested in improving my own driving efficiency and less interested in competing with the world at large.