diff --git a/buildozer/targets/android.py b/buildozer/targets/android.py
index b72a8d5..3b35b7d 100644
--- a/buildozer/targets/android.py
+++ b/buildozer/targets/android.py
@@ -464,6 +464,7 @@ class TargetAndroid(Target):
         if not exists(dist_dir):
             need_compile = 1
 
+        # len('requirements.source.') == 20, so use name[20:]
         source_dirs = {'P4A_{}_DIR'.format(name[20:]):
                            realpath(expanduser(value))
                        for name, value in self.buildozer.config.items('app')
diff --git a/buildozer/targets/ios.py b/buildozer/targets/ios.py
index 7910b0d..3126402 100644
--- a/buildozer/targets/ios.py
+++ b/buildozer/targets/ios.py
@@ -128,7 +128,8 @@ class TargetIos(Target):
         if last_requirements != ios_requirements:
             need_compile = 1
 
-        source_dirs = {'{}_DIR'.format(name[20:]):
+        # len('requirements.source.') == 20, so use name[20:]
+        source_dirs = {'{}_DIR'.format(name[20:].upper()):
                             realpath(expanduser(value))
                        for name, value in self.buildozer.config.items('app')
                        if name.startswith('requirements.source.')}