Hrm nothing has changed on the PGB side recently that would change this. It sounds a lot more like a change to the iOS webview to me. Do you have both versions of the app running on the same device? And each exhibit differing behaviour?
It may not have been a recent change in PGB then, but I don't remember seeing videos being forced full screen last week when I was testing some changes. The live app was built May 18th, 2016 and shows videos inline as we want. When I use those exact same files that were used to build the live app, it opens videos full screen in a new build. I am installing it on the same device (iPhone 6 - iOS 10.2.1). The only difference is the certificate and the any changes in PGB since the live app was built. Would the certificate be doing something weird with it or is this something that PGB is doing differently?
This turned out to be the webkit-playsinline attribute. In some versions of iOS 10, it seems to have dropped support of webkit-playsinline and just uses the unprefixed playsinline attribute. I have set our code to use both and that seems to have fixed the issue. It's weird that it was working on our live app and not on the test app with the same code and device though, but at least I found the issue.
We can't seem to get this working properly with the latest Phonegap Build version.
We've included the preference in the config.xml file:
<preference name="AllowInlineMediaPlayback" value="true" />
And here's the video code:
<video loop muted playsinline webkit-playsinline autoplay id="bgvid">
But yet, no luck. Every time we load up the app in the Phonegap app via ios, it continues to autoplay full screen, rather than inline.