There are many emulator that gives you the ability to test android applications in your computer ( as example see here Android operating system on computer ).
But most of these emulators are usually lag if you have a weak computer. That why, in this post, I will show a wonderful service which helps you to run android applications (games, social network apps...) online.
Manymo is between the best emulators which offers free android emulation online.
How to have access to this service:
First, go to this address: Manymo sign up
Register to manymo, then wait for an activation link, to activate your account.
After the activation, go this address => Manymo emulators
There are many sizes. You can choose whatever size you want.
How to test applications:
Go to this url => click here ( you must be logged in )
Then upload an apk android file as you see in the picture below.
If you don't have an application in your computer, here is one ( whatsapp ).
If you finished uploading, you will be you redirected to launch page in which you can choose your customized size.
Have fun. please don't hesitate to post comments below.