What is the Universal Calibration for Android smartphones?

Each Android smartphone has different types of hardware; their specifications are not universal to other smartphones on the market between manufacturers. Over time, EyeQue has been testing many Android-based smartphones and has developed a universal calibration for Android devices.  The primary factor that EyeQue calibrates the Personal Vision Tracker (PVT) and VisionCheck to is the pixel per inch density (PPI), or the space between the pixels, of the smartphone’s screen.  Our software and optical teams have devised a universal calibration to work with Android smartphones that have a PPI greater than 250.  That means no matter the model, manufacturer or type of Android smartphone you will be able to use either the VisionCheck or PVT as long as the PPI is higher than 250.  After testing, we found that those smartphones with a PPI lower than 250 can have a result that is a full diopter or more off making it less accurate and unreliable.  If you do not know your smartphone's PPI you can use this PPI calculator located here to determine the PPI of your screen.  All you need to know if your screen size and the maximum resolution of your screen.

EyeQue also includes a PPI calibration tool within both of the VisionCheck and PVT applications for Android. Place the VisionCheck or Personal Vision Tracker within the center of the dotted rectangle on the screen. 

If your device sits within side the area with the lines lining tightly outside of the VisionCheck or PVT, you can move to the next step by selecting "yes." If it does not, tap "no" and you'll need to use the + and - keys on the screen to increase or decrease the size of the area until it fits snugly around the edges of your device.

Once it fits snugly, tap the next button and your device will be calibrated properly. If you need further support with the PPI of your device or the calibration of the app, please contact our support team ([e-mail]).