If you own a Jeep, you already know that the modification bug bites hard and fast. You lift it, throw on some 35-inch tires, maybe re-gear the axles—and suddenly, your speedometer is off, your shift points feel sluggish, and your dash is screaming at you about low tire pressure. In the old days, you had to pay a dealership an hour of labor just to flash your computer, or you had to drop hundreds of dollars on a bulky standalone programmer. Enter OBD JScan, a powerful smartpho