Step 1: Height & Width
Measure the height and width of your device (if you use a case, please measure the total height and width including the case)
Step 2: Thickness
Measure the thickness of your device (don’t forget to include the case if you use one).
Step 3: Find your size
Medium is best for standard size phones like an iPhone (and similar) while Large is best for larger phones like an iPhone Pro Max (and similar)