How to see RAM usage in Windows Phone?

I wonder how much RAM is used by each app in my Windows Phone. There is no system application in Windows Phone to check RAM usage. Only way to know your phone's RAM usage is installing a third party apps. I found this app Hardware Tests which is able to show memory usage. This app is compatible with Windows 8 and Windows 8.1

App name - Hardware Tests
Price - Free
Download Link - http://goo.gl/Smb1dm

How it works:

This app is packed with all Windows Phone utility. This one app is enough to check all the hardware information of your Windows Phone. With just 2 MB this app can do the following tasks.

• Speaker test
• Microphone test
• Advanced speech and TTS test and information
• LCD Screen tests
• Touch screen test
• MultiTouch test
• GPS test
• Vibration
• Compass
• FM Radio test
• Accelerometer , Inclinometer, Orientation sensors
• Camera
• Flashlight

It also provides information about your phone, camera and storage. It takes almost 10 apps to get all those information mentioned above. Here you will get all the information at your finger tips. I can say it is a simple tool to get all the information about your phone. I downloaded this app to know free space available in my SD card. But after installation I was impressed with the functions provided by this app. 

How to use:

Once you open the app you will find various tile icons. By the name you can figure out the process. Just click on any tile icon to get the information of your Windows Phone hardware. 

This app is like Device Manager in Windows PC versions.