Touchless Locking and Unlocking a Smartphone Touchscreen - The Beginning

The Main Idea
Most smartphone owners and users are rarely ever out in the world without their trusty mobile device by their side.  During most interactions with our smartphone, we have the luxury of being able to use the touchscreen or voice commands to activate its functions.  There are also many situations where a discrete sneak peek at new text or email is necessary.  Imagine the following context.  You're in a really important meeting and you're supposed to provide your full attention.  But, this might be that really important email that you've been waiting for.  Don't really want to be tapping, scrolling and make it blatantly apparent that you're checking your phone when you shouldn't.  Voice commands don't help too much, the last thing you want it to let the whole room know that you're checking your email during an important meeting.
Added Benefits
Our invention was also designed with some other key benefits in mind.  With most normal use, locking the phone when idle is left up to a "time out" function where the screen turns off after the phone hasn't been used for a set period of time.  Now, this can become an annoying function, especially if you're reading something or playing a game where you're not scrolling, moving the phone or anything else.  Right in the middle of something important, the screen goes blank and you have to unlock the phone again.  Another area that our invention really helps out is prevention of the accidental "butt dial/text/email."  We're constantly astounded by the number of people we know who forget to hit the power button to lock the screen.
 A Touchless, Gesture-Based Solution
Solving all of these problems requires a solution that is able to lock and unlock the phone screen instantaneously, by recognizing a gesture that tells the phone "hey, wake up, I want to use you!" and "OK, it's time to go away."  Really, the only solution that we're left with is a touchless method, where the phone is able to recognize from a gesture that you're trying to engage or disengage with your smartphone.
To figure out a solution, we first spent a little time watching what people normally do to engage with their smartphones.  One consistent gesture that we noticed is that people put their phones aside on a table then lift the phone up to their face so that they can see the screen.  This is an action that people generally perform while sitting down.

Here's one way that we engage with our phone. We pick it up off a surface and make the screen available for viewing.

A second movement that was very consistent is that people tend to take their phone out of a pocket or bag while standing up.  Once again, the hand brings the phone upward and turns the screen toward the face.

Here's another way that we normally engage with our phone. It comes out of the pocket, or bag, and once again, it is turned toward our face so that we can see the screen.

An interesting discovery that we made was that most people disengage with their smartphone by performing the exact opposite movement that they used to engage with it.  This made matters a lot easier, meaning that whatever algorithm is able to detect the gesture to engage only has to be reversed in order to provide the locking function.
In our next post, we'll cover the analytical issues that were required to begin to develop a method of clearly identifying the locking and unlocking gestures required to make the invention work.