There is an app I use quite a bit on Windows called Clock Stopper. All it does is freeze the computer's clock so apps and such are all dated at the same time when installed. It would be awesome if something like this was available for Android.
Why? Because I like to try LOTS of new apps. It would be easier to freeze the clock at a certain date & time, install the apps, create a backup, etc. It makes it easier for me to remember when and what I did.
Also some apps have time restraints on them when I want to use them longer before I decide to buy them.