Where can I find the .apk file of an application on my device, which I downloaded and installed from Google Play Store. Just in case I want to send it to one of my friends through Bluetooth etc..,??
There is an app in google play known as MyAppSharer. Open the app, search for the app that you have installed, check apk and select share. The app would take some time and build the apk. You can then close the app. The apk of the file is located in /sdcard/MyAppSharer
This does not require rooting your phone and works only for apps that are currently installed on your phone