Piston (OBD2 & ELM327)

Simple, Fast, And Useful. This app does exactly what I need it to do. It may not be as in depth as other apps, but it works very well. The interface is easy to use. Works well with "Generic Bluetooth OBD2 interfaces". It retrieves and clears codes faster than other apps (torque) IMO. There is even enough to get you started with basic troubleshooting (Fuel trims, AFR, etc..)

After having tried many of the more popular OBDII apps, this is the one I stuck with. Clean interface, the UI is simple to navigate, and no irritating ads. Connected quickly to my BAFX Bluetooth scanner and easily cleared and found issues. 4 stars given for inability to locate MAP sensor issue, but to be fair, similar apps did not find the issue either.

Wow!!! I have gone through downloading and experimenting with 25 different apps. All of them free. Piston app blew me away. Gives you more than 4 other apps combined. I've been a Tech for 24 years. This apps rocks! I can get 10 or more seperate live parameter feeds streaming! In real time. Man what deal. I'm impressed. Thank you, thank you. I'm done searching.

IT WORKS. 2004 USA spec Mazda RX-8 with a BAFXPRO obd adapter. After 2 hours of trying ~10 of the most popular (Freemium and paid) CAN bus reading apps.. and their subsequent complete and utter failure to connect to my cpu...BOOM! A FREE ..not Freemium app comes along and JUST WORKS! Marcin, buddy, you rock. Let me know how I can paid you something.

Of the 8 OBD II apps we tried, this one was the most reliable in terms of communication. The only thing lacking is it would be nice to have analog gauges. The biggest flaw with this app is that the Metric/Imperial setting applies to all measurements: that's no good here in UK where we mostly use Centigrade, but also use miles per hour!

Very easy to use on Golf GTI, no ads and the live vehicle data is like no other (especially to check if the alternator is charging). If this app was able to CUSTOMISE options in the car (like Carista) it would be incredible and I would be willing to pay a one-off fee for it. Love how it's easy to use and free. Thanks for such a good app.

I love this app. But it cannot be completely closed and will prevent other OBD app to get data. I have two apps just in case. Hope this will be solved.

Just add some theming and a way to get fuel level and you have the perfect obd app. Its not bloated and connects with my Bluetooth elm straightaway no questions asked.

I love that this app doesn't ask for access to everything on my phone! It works great. Simple, intuitive interface. Wish it did some graphs, but no biggie.

Easy setup. No BS. Quick selections. No brainer to use this app... Update- the for dummies version for OBDII. This app's for grease monkeys, positively love it. Do more nerdy apps!!

Sadly this app failed to pick up anything other than voltage from the ELM v1.5, even after five minutes with the engine running, where as many other free OBDII apps detect up to 14 OBD variables from this vehicle.

Strong and simple ui app really ez to use for not experienced users just great , is there a way throw mode 6 codes? It is possible to add this in this kind of app? Thanks in advance

Mate, thank you for a free and functional diagnostic app. Dose what it says,love how it works with obd Wi-Fi and bluetooth scanners. If your in Sydney please allow me to buy you a case of beer for your efforts A1app.

Great program. I have a audi a6 2009 tdi and in live data almost nothing is available.would like fuel level.boosy...etc.

E-mailed dev for support that it was not connecting to my OBDII BT dongle, never heard back from support. Has application been abandoned?

Not bad for a free Obd 2 App. I use often with elm bluetooth. Does not work well with BMW though.

Connects to Bluetooth then immediately disconnects.

Best free app I've ever used no ads... Thank you for helping others when the world doesn't care. Now how can we help you with keep making free apps if we are able.

Unlike other obd reader apps (torque), no issues to connect to Vgate ELM by bluetooth and require min. authorization to phone. It works and simple to use. GREAT APP!!

raw interface data log is neat though

Bought a $20 adapter from amazon and can now read and reset check engine codes. Used a veepak bluetooth adapter and was on an Audi A4. S5 running marshmalllow. Also connects incredibly fast.

Just add some theming and a way to get fuel level and you have the perfect obd app. Its not bloated and connects with my Bluetooth elm straightaway no questions asked.

This was the only app that was able to read the error code for a 2015 Ford Focus ST. I had tried Torque, OBD Auto Doctor and E OBD2 before with no luck. I used it with a PLX Devices Kiwi 2 scan tool.

Excellent. Works every time, clean interface. WiFi connection capability (which not all android apps have). I've tried 6 or 7 OBD2 apps, paid and free, and this is my favorite.

Can not scan for codes.. keeps loosing connection. Live works

Works just like expected. Took 5 minutes to setup. App looks great unlike other obd2 apps.

Brilliant. Kept me on the road when all else failed!!

I tried it on my 4 cars and all 100 of the cars and trucks at my buddies used car lot the app never once connected to my obd2 dingle when other programs will, this app is a waste of time.

Works one ever thing

Tried a couple of others and this one connected, worked, and was not limited to only 2 parameters/sensors. Yea!

It even resets error...

With delphi diagnostic

Would have really if there was an option for recording. This is only program working with my civic 2000.

Worthless nonsense hence the price.

Very good app and clean interface. I'd love to be able to view o2 as actual afr tho.

If you just want to read and reset fault codes this is the app for U. It connects real fast and tells U the Obd2 fault codes. But there is not much on diagnostics. But then the app is free and you do not even have to pay for an expansive adapter.

Connected well to my wifi iobd on andriod. Read all errors I wanted to see. I recommend to move Settings button to left floating menu. My respect to developer.

I tried 10 or more apps and got *nowhere* with my 2005 Cary. With 'Piston' I am able to read everything *and* was able to reset my 'Check Engine' light! Yay!!

Piston connects every time. The interface does exactly what I want it to do. It will tell me things about my car that I never thought to ask. Consistently reliable. Easy to use.

Just like some other users have noted; this app is solid and reliable; connects quickly, displays nicely and simply works. Simple interface and good features. Use it!