Idea of Upload to Cloud Filled Icon
The icon for upload to cloud is a cloud with an arrow pointing up. Since you are loading the images on a cloud service the arrow pointing up represents the images going into the cloud system that keeps the pictures out of your device but still easily accessible.
This is a Upload to Cloud Filled 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 13,900 icons, all in the same style and quality.