2D Game Character Design and DPI

Hi, I’m trying to design 2d game characters in PS to put the asset store.
I am a newbie on this area, and need your help to decide the DPI value.
Is DPI matters for mobile/web games? I used to pick 72DPI for ‘1920X1080’ resolution.
But nowadays, I understand DPI values of the new screens may vary up to 400dpi.
Which DPI value should I pick for 1920X1080 resolution?

Bigger gives people the option to downsize it themselves.