Minimum size of buttons for mobile APP [duplicate]

1. What size should mobile buttons be?
2. How many pixels should a button be?
3. How big should buttons be iOS?
4. Should mobile buttons be full width?

What size should mobile buttons be?

Studies by the MIT Touch Lab suggest that 10mm × 10mm is the best minimum size for buttons on mobile due to the average size of fingertips.

How many pixels should a button be?

Button size should not be less than 42 pixels and a maximum of 72 pixels. The most preferred button size is 60 pixels at a minimum, with 72 pixels optimal for certain users. Looking at research studies, a 72 pixel button was preferred by older users and overall produced the highest touch accuracy.

How big should buttons be iOS?

Buttons are by default dynamic in width and are dependent on the container they are placed in, but they can also be set to a fixed width and height. A touch area of a button should not be less than 44pt.

Should mobile buttons be full width?

Depending on layout, orientation and purpose but it's a good rule of thumb to add at least an 8dp margin. Keep in mind touch space limitations, for example on Android, Material Design deems as good practice to have buttons that are at least 48x48 dp wide so the area of the buttons is comfortable to use for the users.