These cheaper headsets do not have any electronics or built-in computing power—all of the processing and image rendering is done by the smartphone. This keeps the cost of the headset itself very low, but a cardboard headset can have some disadvantages. For example, cardboard might not be as durable or as comfortable as other materials like plastic or rubber, and it could be easily prone to staining from the user's sweat.

Can you do an engineering project where you either modify an existing Google Cardboard headset to improve it (a variety of headsets are available from Amazon.com), or build your own headset from scratch? See the reference in the Bibliography for official specifications and dimensions for Google Cardboard headsets, and note that you can purchase compatible lenses online. There are many ways you could improve or redesign a headset. Here are just a few suggestions:

• Design a headset with padding that is more comfortable to wear.
• Design a headset that is easier to clean—who wants to share a sweaty headset with a friend?
• Design a headset with grips that are easier to hold for extended periods of time.
• Design a head strap for your headset so you do not have to hold onto it during extended use. Note that the official Google Cardboard specifications say not to use a head strap because they can cause motion sickness (you cannot move your head as quickly if you are holding the headset with your hands and thus have to rotate your entire body), but most gaming headsets do have head straps.
• Design a better input mechanism for the headset (for example, a magnetic slider, conductive touch sensor, or Bluetooth-enabled button).

Make sure to test and evaluate your headset by following the engineering design process. For example, you could recruit volunteers to try out your headset and see whether or not they like the new features.