Never judge a girl by what she can do with her hands. Instead, judge her abilities for what she can do with anything but her hands. Like her feet, for example. You'll know there's nothing she can't do if she can control her lower limbs with the same dexterity as her hands.
You can't exactly tell a girl to peel a banana using her feet outright. That's why you've got the Showboatr to help you out.
Showboatr is an iOS app that contains a series of challenges that you're supposed to complete while recording a video of the task as you do it. You know, for evidence. But like I said, you could get creative with it and make a girl do what you want her to, without exactly telling her what you want her to do.
Aside from that, it's all good fun. You can even earn (and retain) some bragging rights in the process.
Check It Out: iTunes App Store