This is a iOS Application Placeholder icon. We've made it in iOS style, first introduced in iOS version 7 and supported in all later releases up until now (at least iOS 11). This style is based on thin two-pixel lines and is optimized for 50x50 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 12,500 icons, all in the same style and quality.
It is a little place to put the IOS apps that you download. It is a square box made out of dotted lines where you can put your newly downloaded apps so that they will not be sprawled out all overy our home screen, creating pages and taking up space.