Pretty simple. Go to My Apps at the Play store then tap on the All tab. You can touch and hold to highlight an app. Once you do that, all the apps installed on your device are greyed out. You can tap on any of the other apps to highlight them. Slide down the list and tap any other apps you want to remove. When you're done, just tap the X at the top right and all the highlighted apps will be removed from your list. It will remove apps from the list that you have installed on other devices.
If you are someone who installs a bunch of different apps to try then uninstalls them, this is an easy way to track which ones you use, especially if the apps have similar names.