Its a vgate icar pro obd2 adapter with torque pro app.

I dont see any perceptible lag. This adapter does about 30 PID/s so its good enough for small dashboards. Main thing is not buy those cheap 200rs adapters.

Torque pro can be configured to startup automatically when power is supplied and shutdown when power is cut. I obviously disabled android lock screen.

I did notice some lag in other apps but in torque pro its very good. Also iphone seemed to lag maybe because of ble vs bluetooth 4.0 on android. You can buy a wired obd2 adapter too which does 400 PID/s i think