This is why I'm all for the future of apps being web-based. Write once, and able to run everywhere.
The web is already almost as closed (for apps) as phones are - you can choose Chrome, Safari if you're on Mac, or Firefox. Everything else is just repackaged Chrome. Edit: forgot Opera Mini, for what it's worth.
Firefox is dying out, and Google is pushing for less and less user freedom in Chrome, while Apple is extremely reluctant to implement new features that make Safari a better app platform.
Web Bluetooth
Web MIDI API
Magnetometer API
Web NFC API
Device Memory API
Network Information API
Battery Status API
Ambient Light Sensor
HDCP Policy Check extension for EME
Proximity Sensor
WebHID
Serial API
Web USB
Geolocation Sensor (background geolocation)
User Idle Detection
Note: I do understand Apple's privacy concerns with some or even most of them. But most of these are obviously necessary if you want to turn the browser into the main application platform, for better and for worse.What? Nobody needs permission to publish a webpage, while every week we hear about google or apple blocking or unpublishing apps with flimsy justifications.
(Likely wrong terminology but you hopefully get the idea)