How to get application usage statistics on android?

Question

What I want is to access the time (in milliseconds) that each application is used.

Thanks

Answer 1

Dig up the source to "Spare Parts" and see how they do it

(also copy it off the emulator, install it on your phone and make sure it works)

Note: while this remains accurate for the circa-2010 versions of Android about which it was written, restrictions added years later in 4.4 and 5.0 would substantially frustrate achieving this in more recent versions.