Arduino memory and android?

Hello,

I am new to Arduino. I noticed that when I plug in the usb cable to the arduino it automatically runs the code of the last project used. How can I stop this because it seems dangerous?

Also I used ArduinoDroid for the first time on my nexus 7 tablet. My code and project worked perfectly. I'm wondering if this could potentially harm my android device if something goes wrong, like taking too much power or something.

Thanks

When I first connected my Arduino to the Android tablet it asked if I wanted Arduinodroid as default app for this. I think I said no, maybe you said yes and Android recorded somewhere Arduinodroid as default app, as you can do for PDF files, email, browser, ecc... Does it sound?