Question

How do I keep track of the runtime of an application.

Answer 1

What do you mean by runtime? The time elapsed after you launch an application?

I don’t think there is any direct method that can give you the elapsed time. You can maintain a timer on you own.

You can also use System.nanoTime() to get the most accurate timing.

long startTime = System.nanoTime();    
// ... the code being measured ...    
long estimatedTime = System.nanoTime() - startTime;

Edit—

Yes i think Ben is correct.. If you want to just measure how long a process is running then you can try using this approach
android.os.Process.getElapsedCpuTime() – This should return the elapsed milliseconds your process has run. I believe your application also should run on a unique process ID. So that time should be fine