On the table is a mobile phone and balloon.
Inflate the balloon. With a quick gesture, press the balloon onto the phone while simultaneously leasing the air from it.
The phone appears inside the balloon.
You give the audience a good look at the phone in the balloon.
Now you can tear the balloon, freeing the phone. Or, inflate the balloon again and the phone flies out.
You show your audience that the inflated balloon is whole.
The secret to the magic trick is, after all, that the balloon simply “shrink” wraps itself onto the phone, giving the impression that the phone is inside. When showing the phone to the audience, cover the back side with your hand so as to not spoil the illusion.