Since Expo has released SDK 40, we are obligate to migrate to submodule expo-notifications. It is the right way of development, but this library seems to have some problems, which we have to face up to.
Unfortunately, from time to time, I face some problems with my credentials for PUSH notifications. When I try to send PUSH through Expo PUSH Broadcaster, it responds with an error "Could not find APNs credentials for {bundleIdentifier} (@{user}/{app_slug}). You may need to generate or upload new push credentials". When I am writing this - I have no idea why it is happening, but I know how to fix it fast.
Apple released new Xcode with new, shiny simulator. And thanks for that, we can now test our PUSH notifications without real device!
Expo doesn't support only development, it helps us also in building and publishing process, by preparing packages for Android and iOS. We have to only upload our sources to Expo cloud and after a few minutes, our application is ready to download. And this is the moment when you want to consider standalone Expo build.