Compiling answers given by @adurdin and @User
Add followings to your info.plist & change localhost.com
with your corresponding domain name, you can add multiple domains as well:
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsArbitraryLoads</key>
<true/>
<key>NSExceptionDomains</key>
<dict>
<key>localhost.com</key>
<dict>
<key>NSIncludesSubdomains</key>
<false/>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<false/>
<key>NSExceptionRequiresForwardSecrecy</key>
<true/>
<key>NSExceptionMinimumTLSVersion</key>
<string>TLSv1.2</string>
<key>NSThirdPartyExceptionAllowsInsecureHTTPLoads</key>
<false/>
<key>NSThirdPartyExceptionRequiresForwardSecrecy</key>
<true/>
<key>NSThirdPartyExceptionMinimumTLSVersion</key>
<string>TLSv1.2</string>
<key>NSRequiresCertificateTransparency</key>
<false/>
</dict>
</dict>
</dict>
</plist>
You info.plist must looks like this: