Launching applications in Android

To launch an application programmatically in Android given an ApplicationInfo, do:

ApplicationInfo ai;
PackageManager pm = getPackageManager();
try {
    Intent i = pm.getLaunchIntentForPackage(ai.packageName);
    startActivity(i);
} catch (Exception e) {
    Toast t = Toast.makeText(this, "Couldn't launch the application.", Toast.LENGTH_SHORT);
    t.show();
}

Apparently this was harder pre-1.5, where you had to look for the proper activity yourself.