报错：Could not build the precompiled application for the device.
It appears that your application still contains the default signing identifier.
Try replacing 'com.example' with your signing id in Xcode:
open ios/Runner.xcworkspace
Error launching application on iPhone.
解决方案：
按照报错提示，在terminal中输入
open ios/Runner.xcworkspace
点击
按照顺序进行点击，如果没有，进行注册一个免费的appstore账号
手机上要进行开发者证书进行Trust一下