打开iPhone设备的设置程序。 点击通用。 点击存储和iCloud用量。 点击“存储”部分下方的管理存储空间。

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It's the grey gear icon that's likely on the Home Screen. Due to operating system restrictions, you can't view your iPhone's RAM usage. You should see this option toward the bottom of the screen. It's toward the bottom of the screen. This section is at the top of the page. Doing so will open a list of your device's apps in order of most space taken up to least space taken up, along with "Used" and "Available" sections at the top of the page that display your iPhone's used space and free space, respectively. Tapping the second Manage Storage on this page will open the iCloud page where you can see how much room remains in your iCloud Drive.