> Back in the day, applications on Symbian devices could run in background without any indication.
This was absolutely terrible for battery life, though. Accidentally leave the IRC client open in the background? There goes your battery. There are non-nefarious reasons why smartphones work they way they do nowadays.
But they did it less for saving battery life and more to push their own Software. There are many things that could have been done to avoid the battery issue.
They changed API to clearly show that an app is using battery to push their own software? Who's "they" and what kind of conspiracy theories have you been reading again?