Below are the basic asset requirements for an Event App
App Logo - 1024 width x 1024 height px; JPG; Max size 5MB
App Name (Upto 15 characters)
Splash Image - 1080 width x 1920 height px; JPG; Max size 5MB. If you are adding any content (text etc) to the splash image make sure to give a margin of atleast 150px on all sides for the best positioning.
Splash Gif (Optional) - 1080 width x 1920 height px; GIF; Max size 10MB