cordova - can I detect slow device in phonegap -

I am creating a phonegap application that has a page slide function. It works fine on fast devices, but it is low on slow device and gives users poor experience, so I have given a version which is not so beautiful, but it works better on a slow device.

Now my problem is, I can not find any way to find out if the device is slow or not. I can probably check the API version on Android, but the older Samsung 4.2.2 is running, so this will not do the trick.

So how can I locate a slow device in PhoneGap?

Cheers