You can choose how many columns you want show in each device. Test it with your mobile device.
The settings for this gallery are this (you can choose other value, this is only an example):
Smartphone portrait: 2 columns
Smartphone landscape: 3 columns
Tablet portrait: 2 Columns
Tablet landscape: 2 Columns
Desktop => 640px and <= 1024px : 3 Columns
Desktop <= 639px: 2 Columns
