Android application package file (APK) is the file format used to distribute and install application software and middleware onto Google’s Android operation system. Apk file are zip file formatted packages based on the Jar file format, with dot (.) apk file extension.
For create apk file you have need to create a key store for
Here I am telling you how to create signed apk file in eclipse
1. Go to the File menu choose Export Android Application.
2. Now choose your application
3. After add your application, then press Next. Now choose your key store location if you have already key then select Use existing keystore and if you have no keystore then select Create new keystore. First of all browse your location for store key and type your keyname for example key name is sample
4. After choose your location and now fill below steps and click in Next button
5. Now choose your location for storing apk file then select Finish button. After fulfil these steps you can see your apk file in your desired location.