Add an app to the Google Playstore installed list I have recently have had to flash my GApps package on Cyanogen. As a result all the application that were previously listed in the installed apps section are no longer present any more. 

Is there any way I can add them back there so that PlayStore will continue to track updates for them ?
You can use Titanium Backup's Market[sic] Doctor feature to restore your apps to the 'Installed' list in Google Play Store. Here's how:


Open Titanium Backup.
Press the Menu button on your device.
Select Market[sic] Doctor .
From the popup, select User apps or User and system apps depending on which kind of app isn't showing up on your 'Installed' list.
Select all apps from the list that will show up, or choose just the ones you want to show up in Google Play Store, then select Done in the upper-right corner of the screen.
Wait until the operation finishes.
Open Google Play Store's Installed list and your apps should be there.


Cheers.