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+#  CustomDNS
+
+This is a sample app that configures a DNS-over-TLS resolver to the system. `NEDNSSettingsManager`, added in iOS 14, iPadOS 14, and macOS Bug Sur, makes that possible.
+
+## Steps to Use
+
+### In case of iOS/iPadOS
+
+1. Open this app once
+1. Open the Settings
+1. Go to "General" > "VPN & Network" > "DNS"
+1. "Automatic" is selected by default, so select "CustomDNS"
+1. Force-quit and reopen this app
+1. If "Enabled" is displayed, the configuration is successfully enabled
+
+### In case of macOS
+
+1. Open this app once
+1. Open the Preferences
+1. Go to "Network"
+1. I don't know how to use it yet
+
+## References
+
+- https://developer.apple.com/documentation/networkextension/dns_settings
+- https://developer.apple.com/wwdc20/10047