iOS WatchKit - Error launching watch app "SPErrorInvalidBundleNoGizmoBinaryMessage" -

i trying build watchkit app allow two-way communications between iphone app , watch app. have setup app groups , proper app certificates, provisioning profiles , entitlements set , match up. keep getting error when try run watch app (no error when running iphone app).

error:

error launching 'mywatchapp watchkit extension' sperrorinvalidbundlenogizmobinarymessage

i think has bundle identifiers, far can tell looks correct. suggestions?

here bundle identifiers:

app group key: group.com.nitwitstudios.mywatchapp  iphone app bundle identifier: com.nitwitstudios.mywatchapp  watch app bundle identifier: com.nitwitstudios.mywatchapp.watchkit watch app wkcompanionappbundleidentifier: com.nitwitstudios.mywatchapp  watch extension app bundle identifier: com.nitwitstudios.mywatchapp.watchkit.extension watch extension wkappbundleidentifier: com.nitwitstudios.mywatchapp.watchkit 

note - changing watch extension app bundle "com.nitwitstudios.mywatchapp.watchkit" allows me run app, never proper results when trying communicate phone -> watch. specified bundle identifier problem in why won't app groups work inside watchkit extension?

i have tried following no success:

• clean / clean build folder
• deleted derived data
• restarted xcode

i using simulator ios8.2; switching ios8.3 worked.