I am using Adobe PhoneGap with Cordova cli-6.5.0 and Apple install in a development mode. On an iPad 2 (iOS 9.3.5) the app works correctly on launch, but on an iPhone SE and an iPhone 7 both running current iOS 10.3.2 the app will not launch until I swipe up and bring the Control Center up. Not sure if it is an iOS version issue or device issue.
Same bug occurs whether the app is in Airplane mode for offline page or online to begin the app. My guess is onDeviceReady is not responding on the iPhone test until the Control Center is brought up.
Add "gap:" to the "default-src" directive in your Content Security Policy (CSP) meta tag. That should address the issue.
I updated my index.html file to use the following, and it now works - thanks so much:
<meta http-equiv="Content-Security-Policy" content="default-src * gap://ready file:; style-src 'self' 'unsafe-inline'; img-src 'self' data:; script-src * 'unsafe-inline' 'unsafe-eval'">