Android: List all installed apps and get total running time of each app

Add this permission to your Android Manifest file:

<uses-permission android:name="android.permission.QUERY_ALL_PACKAGES"/>

And after that you can get a list of apps installed with this function:

public static List <ApplicationInfo> getUserInstalledApplications(Context context) {
    final PackageManager packageManager = context.getPackageManager();
    List < ApplicationInfo > installedApplications =
        packageManager.getInstalledApplications(PackageManager.GET_META_DATA);
    for (ApplicationInfo appInfo: installedApplications) {
        //Do what you want with app info
    }
}

You can get a list of each service's start time by using ActivityManager.RunningServiceInfo.activeSince.

ActivityManager activityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
 List<ActivityManager.RunningServiceInfo> services = activityManager.getRunningServices(Integer.MAX_VALUE);

 long currentMillis = Calendar.getInstance().getTimeInMillis();        
 Calendar cal = Calendar.getInstance();

 for (ActivityManager.RunningServiceInfo info : services) {
     cal.setTimeInMillis(currentMillis-info.activeSince);

     Log.i(TAG, String.format("Process %s with component %s has been running since %s (%d milliseconds)",
             info.process, info.service.getClassName(), cal.getTime().toString(), info.activeSince));
 }