Since the plugin's methods return already a promise, the workaround with the `sync` option was used. This worked well for the method calls. However, when either cordova or the plugin was not available, an error was thrown, instead of rejecting the returned promise.
Therefore a better way is to use the `otherPromise` option, introduced with https://github.com/driftyco/ionic-native/releases/tag/v1.3.8.