As noted by Michael Steeber, who found the hidden feature, typing in “10 years” sends two blue balloons soaring up from the bottom of the screen.
The balloons will bounce around for a few moments, and if you tap them, you can pop them. Otherwise, if you leave them alone, they’ll simply float away.
You can re-summon the balloons by typing in the phrase again. Make sure to use the Apple Store app, where you make Apple device purchases and view orders, to try the trick.