AppRTCMobile links against framework target.

webrtc/sdk/BUILD.gn

 # Copyright 2016 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("../webrtc.gni")
 if (is_ios) {
@@ skipping 299 matching lines @@
       ]
 
       sources = common_objc_headers
       public_headers = common_objc_headers
 
       if (!build_with_chromium) {
         sources += [ "objc/Framework/Headers/WebRTC/RTCFileLogger.h" ]
         public_headers += [ "objc/Framework/Headers/WebRTC/RTCFileLogger.h" ]
       }
 
-      ldflags = [ "-all_load" ]
+      ldflags = [
+        "-all_load",
+        "-install_name",

[daniela-webrtc, 2017/01/26 07:44:24]

I'm not familiar with this flag. What is it suppose to do?

[kthelgason, 2017/01/26 08:31:48]

In short, it has to do with how macOS loads dynamic libraries. Dylibs have a
load command that specifies their install_name, and this is what the application
that links against them will look for when loading them at runtime. The
application also has a load command specifying it's @rpath, where it will look
for libraries to load.

+        "@rpath/$output_name.framework/$output_name",
+      ]
 
       deps = [
         ":rtc_sdk_peerconnection_objc",
         "../system_wrappers:field_trial_default",
         "../system_wrappers:metrics_default",
       ]
 
       libs = [
         "AVFoundation.framework",
         "AudioToolbox.framework",
@@ skipping 61 matching lines @@
       deps += [ "$rtc_libyuv_dir" ]
       public_deps = [
         "$rtc_libyuv_dir",
       ]
     } else {
       # Need to add a directory normally exported by libyuv.
       include_dirs = [ "$rtc_libyuv_dir/include" ]
     }
   }
 }