AdNetwork Plugins Other Linker Flag Issue

I am using AppLovin and Admob ads in my game. I am facing problem while creating build for iOS. I have recently updated AdMob plygin to 7.0 and now start generating list of problems related to Other Linker Flag.

If I do not specify -ObjC in Other Linker Flag attribute then project got compiled but crashed during runtime.

2015-03-30 22:17:56.227 feedmachi[13654:1803] Warning: the -ObjC linker flag was not set in your project - this is required to use a static library such as the AppLovin SDK. Please update your Xcode project's Build Settings -> Other Linker Flags to include -ObjC.

If I specify -ObjC in Other Linker Flag attribute then project not compiled at all.

ld: 444 duplicate symbols for architecture armv7 clang: error: linker command failed with exit code 1 (use -v to see invocation)

What is the solution for this? Please give some suggestion in this. I really need it.