Installing APK into Android Emulator/Devices

Directing Commands to a Specific Emulator/Device Instance

If multiple emulator/device instances are running, you need to specify a target instance when issuing adb commands. To so so, use the -s option in the commands. The usage for the -s option is:

adb -s <serialNumber> <command> 

As shown, you specify the target instance for a command using its adb-assigned serial number. You can use the devices command to obtain the serial numbers of running emulator/device instances.
Here is an example:

adb -s emulator-5556 install helloWorld.apk

Note that, if you issue a command without specifying a target emulator/device instance using -s, adb generates an error.

Installing an Application

You can use adb to copy an application from your development computer and install it on an emulator/device instance. To do so, use the install command. With the command, you must specify the path to the .apk file that you want to install:

adb install <path_to_apk>

Note that, if you are using the Eclipse IDE and have the ADT plugin 
installed, you do not need to use adb (or aapt) directly to install your
application on the emulator/device. Instead, the ADT plugin handles the
packaging and installation of the application for you. 

Installing into Devices

If you want to install into devices then just send .apk file using bluetooth/USB and install it. Note that for IOS(Apple) extension will be different and not .apk