HT200

Review by eFreeware

If you own a scan tool or work on cars regularly, HT200 is the app side of that job: a free OBDII diagnostic companion from developer autel2019 that reads fault codes and walks through common service procedures. It is built for people who want to plug in, see what the vehicle is complaining about, and get on with the repair.

The appeal is the scope. The developer says every OBDII function is available at no cost, and the diagnostics run on Autel's own platform. On top of basic code reading, the app covers up to 19 service functions, among them oil reset, electronic parking brake, battery management, steering angle, diesel particulate filter, tire pressure and immobilizer work.

It has been on the Play Store since September 2018 and sits at a 2.8 average from 1,161 ratings, with more than 100,000 installs. That score is worth keeping in mind as you decide whether the free feature set is enough for your situation.

Reading faults and clearing service lights

The core job is straightforward: connect to a vehicle, pull the codes, and see what the modules are reporting. Because the app is built around OBDII diagnostics rather than a single system, it is meant to reach beyond the engine light and into the other modules a modern car runs. For a home mechanic chasing an intermittent warning, that breadth is the difference between guessing and knowing.

The service functions are where it earns its keep for anyone doing their own maintenance. Oil reset covers the reminder that stays on after an oil change. EPB handles the electronic parking brake, which often has to be retracted before brake work. BMS, SAS, DPF, TPMS and IMMO each address a specific job that would otherwise mean a trip to a shop with a dedicated tool.

None of this replaces judgment. The app reports what the vehicle tells it, and interpreting that still falls to you. What it does is put the readout and the reset routines in one place instead of spreading them across several tools.

Reports, records and repeat visits

For anyone working on more than one car, the record-keeping matters as much as the diagnostics. HT200 generates repair reports for the vehicles it has tested, and those reports can be exported as PDF files, which makes them easy to print or send to a customer or a colleague. If you are documenting a repair for someone else, that is a practical shortcut.

The app also keeps a history of vehicles tested before, so a car you have already scanned does not start from zero the next time it comes in. Over months of ownership or a series of jobs, that running record is more useful than a single snapshot of codes.

Auto VIN is the third piece of that workflow. Rather than entering the vehicle details by hand, the app identifies the vehicle automatically. Fewer manual steps at the start means less chance of picking the wrong model and reading the wrong data.

What you get free and what you pay for

The download costs nothing and there are no ads. The developer says all OBDII functions are free, which is the part most people will use first. Where the paid side comes in is coverage: one series of vehicles is included with the initial purchase, and you expand to more with additional in-app purchases.

That structure makes sense for someone who works on a single model line and wants the service functions for it without paying for brands they will never touch. It is less convenient if your driveway holds a mix of makes, because each additional series is another purchase on top of the first.

What is clear is the shape of the deal: free diagnostics, paid expansion.

Setup and what the app needs

Getting started is a matter of the vehicle connection rather than the app itself. HT200 is an OBDII tool.

The one series included with the initial purchase is the other thing to settle early. Before you buy into additional coverage, it is worth confirming that your vehicle falls inside what you already have, because the service functions are tied to the series you own rather than to the app as a whole.

The most recent update, from March 31, 2025, is described simply as bug fixes, which suggests the app is still being maintained rather than left as-is. That is a modest signal, but a relevant one for a tool you might rely on during a repair.

Who this fits

HT200 suits the owner who does their own maintenance on a supported vehicle and wants the service resets without buying a dedicated handheld. It also fits a small shop or mobile mechanic who works repeatedly on one or two model lines and wants the reports and history in a form that can be handed to a customer.

It is a narrower fit than the free download suggests. The diagnostics are open to everyone, but the service functions follow the series you have paid for, so the value depends on how closely your garage matches what you have unlocked. Someone who works across many makes will feel that limit sooner than someone loyal to one.

It is not a strong score, and it tells you to set expectations around the free diagnostic layer rather than assume the paid expansion will be everything you hoped.

A tool for one make, not every car in the lot

I would install HT200 if you want free OBDII diagnostics and a defined set of service functions for a vehicle series you already own. The combination of Auto VIN, PDF repair reports and a history of past scans gives it a workflow that a bare code reader does not have, and the absence of ads keeps it out of the way while you work.

Go in knowing the shape of the purchase. One series comes with the initial buy, more coverage costs extra through in-app purchases, and the app's usefulness scales with how well your vehicles match what you have unlocked. If you maintain a single model line, that is a reasonable trade. If your driveway is a mixed bag, the math changes quickly.

For a free download with no ads, it is easy enough to try the diagnostic side and judge the paid expansion on your own vehicles. That is the sensible way to approach it.

What's new in version 1.64

Fix bugs.