[on_and_off]

For the background WorkManager has done wonders.

For hardware, I believe that 100%. I am talking about "regular" android apps that don't need deep access to the hardware. By deep I mean something harder than recording something (e.g. taking/picking a picture is delegated to the default system app, not the one you build) or displaying the current position with a mapping sdk.

Bluetooth in particular I can believe. It is amazingly complex and adding the OEMs customizations on top must be a total pain.

[pjmlp]

On ADB Podcast about Bluetooth, they referred that certain models would just crash if someone tries to talk with specific protocol versions.