diff --git a/Changelog.md b/Changelog.md
index 7f75719fb..f14718b1e 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -69,6 +69,7 @@ The keys will still be available in the root level within the 0.5 release. The o
 * Fix poll creation on Bootstrap pages [#5334](https://github.com/diaspora/diaspora/pull/5334)
 * Show error message on invalid reset password attempt [#5325](https://github.com/diaspora/diaspora/pull/5325)
 * Fix translations on mobile password reset pages [#5318](https://github.com/diaspora/diaspora/pull/5318)
+* Handle unset user agent when signing out [#5316](https://github.com/diaspora/diaspora/pull/5316)
 
 ## Features
 * Don't pull jQuery from a CDN by default [#5105](https://github.com/diaspora/diaspora/pull/5105)
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index f95636f60..327b6068c 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -36,7 +36,7 @@ class ApplicationController < ActionController::Base
   def after_sign_out_path_for(resource_or_scope)
     # mobile_fu's is_mobile_device? wasn't working here for some reason...
     # it may have been just because of the test env.
-    if request.env['HTTP_USER_AGENT'].match(/mobile/i)
+    if request.env['HTTP_USER_AGENT'].try(:match, /mobile/i)
       root_path
     else
       new_user_session_path
diff --git a/spec/controllers/application_controller_spec.rb b/spec/controllers/application_controller_spec.rb
index 1b2e44ff3..3910e9461 100644
--- a/spec/controllers/application_controller_spec.rb
+++ b/spec/controllers/application_controller_spec.rb
@@ -91,4 +91,11 @@ describe ApplicationController, :type => :controller do
       end
     end
   end
+
+  describe "#after_sign_out_path_for" do
+    it "can handle a nil HTTP_USER_AGENT" do
+      @request.headers["HTTP_USER_AGENT"] = nil
+      expect(@controller.send(:after_sign_out_path_for, alice)).to eq(new_user_session_path)
+    end
+  end
 end