In iOS9, Apple added new feature called App Transport Security(ATS).
ATS enforces best practices during network calls, including the use of HTTPS.
Apple Pre-release documentation:
ATS prevents accidental disclosure, provides secure default behavior, and is easy to adopt. You should adopt ATS as soon as possible, regardless of whether you’re creating a new app or updating an existing one.
If you’re developing a new app, you should use HTTPS exclusively. If you have an existing app, you should use HTTPS as much as you can right now, and create a plan for migrating the rest of your app as soon as possible.
Add Below key in your info.plist & then see.
<key>NSAppTransportSecurity</key> <dict> <key>NSAllowsArbitraryLoads</key> <true/> </dict>
Even you can add specific exception,
<key>NSAppTransportSecurity</key> <dict> <key>NSExceptionDomains</key> <dict> <key>testdomain.com</key> <dict> <key>NSIncludesSubdomains</key> <false/> <key>NSExceptionAllowInsecureHTTPSLoads</key> <false/> <key>NSExceptionRequiresForwardSecrecy</key> <true/> <key>NSExceptionMinimumTLSVersion</key> <string>TLSv1.2</string> <key>NSThirdPartyExceptionAllowInsecureHTTPSLoads</key> <false/> <key>NSThirdPartyExceptionRequiresForwardSecrecy</key> <true/> <key>NSThirdPartyExceptionMinimumTLSVersion</key> <string>TLSv1.2</string> <key>NSRequiresCertificateTransparency</key> <false/> </dict> ... </dict> </dict>