WatchOS app not detecting companion iOS app

Question

I am making an independent Apple Watch app (but with a companion iPhone app which is not necessary for the watch app to function.)

The app uses WatchConnectivity to sync data between devices if iPhone companion app is installed. I am able to call session.updateApplicationContext() on the iOS app and receive session(didReceiveApplicationContext) on the Watch app. But going the other way is not possible. I always get an NSError code of 7018 which means the iOS companion app is not installed.

I have made sure both watchOS and iOS app are installed in simulator (and tested on my actual devices, iPhone 11 & Watch series 5.) But getting the same failed results from watchOS -> iOS.

I noticed there is a new WCSession instance variable available for watchOS 6.0+ isCompanionAppInstalled. When I read this variable after my WCSession is activated on my watch app, it always return false.

Is there anything else I need to look out for? I am thinking maybe there is something I did wrong in all the different info.plist. But I have checked them multiple times.

my info.plist files:

In my watch app:

 WKWatchKitApp is YES
 WKCompanionAppBundleIdentifier is com.abc.myapp

In my watch extension:

  App can run independently of companion iPhone app is YES
  NSExtension
    WKAppBundleIdentifier is com.abc.myapp.watchkitapp
    NSExtensionPointIdentifier is com.apple.watchkit

iOS app bundle identifier is com.abc.myapp
watchOS app is com.abc.myapp.watchkitapp
watchOS app extension is com.abc.myapp.watchkitapp.watchkitextension

Is there anything else I might be overlooking?

Thank you very much for any help/insight you can offer into this.

I have tried to see if I can reproduce this with a brand new project. So I created a new iOS app with watchOS app project in Xcode. And I am getting the same error. Can anyone else reproduce this? I have filed a bug report with Apple. — Cakelly
Delete the key of "App can run independently of companion iPhone app" in Info.plist in Watch Extension works for me — Stoull

Cakelly Cakelly · Accepted Answer · 2020-02-02T23:10:41

Ok. I found a way to get rid of the error and have the watch connectivity work from watch to iPhone.

Originally I wanted the watch app to be independent so in the watch extension target in Xcode, the check box "Supports Running Without iOS App Installation" is checked. But as soon as I uncheck this box, WCSession.isCompanionAppInstalled returns true and error goes away. Syncing from watch to iPhone starts working.

So hopefully this is not intended behavior and will soon be fixed by Apple. (I filed a bug report.) But for now, I am just going to leave the independent watchOS app unchecked because I do want WatchConnectivity in case iPhone app is installed by user.

Thank you for reading and good luck with your programming.

WatchOS app not detecting companion iOS app

2 Answers