Travis: use an existing simulator

.travis.yml

@@ -15,5 +15,5 @@ script:
   # Use `travis_wait` when a long running command or compile step regularly takes longer than 10 minutes without producing any output.
   # It writes a short line to the build log every minute for 20 minutes, extending the amount of time your command has to finish.
   # Prefix `travis_wait` with a greater number to extend the wait time.
-  - travis_wait 30 scan --scheme "Ably" --open_report false
+  - scan --scheme "Ably" --open_report false --devices "iPhone 6s"
   - bash ./Scripts/run_examples_tests.sh