Q:

I need to test my app on different virtual devices

So I'm currently helping to develop an app and I've been asked to test it on as many devices (virtual/non virtual) as possible and then make it adjust it to as many different screen sizes and even tablets as possible. 
Now I'm not sure where exactly to start because I don't know if Android Virtual Device Manager in Eclipse has every possible screen combination.
So, would setting up and running all of the 21 virtual devices in Eclipse do the job? Or is there something else I should try doing? Any kind of information would be helpful, thank you!

A:

If you need to test for specific devices, Samsung has a remote test lab, this way you can test real devices virtually and a large variety of devices.
Additionally, you can use the Amazon Device Farm which has Samsung phones as well as other Android, Fire, and iOS phones.

A:

And another testing service with real and virtual devices that you can remotely control is testobject
It is just for Android apps at the moment, but still a really nice tool to test with.

A:

There's a few mobile app testing services that are available.
These services include remote virtual access to most major devices available.
Note these are real devices and some actually have live connections to some of the most popular telecoms.
Here are three of them:
Perfecto Mobile
KeyNote DeviceAnywhere
Less Painful

