The result of a company's attempt to reduce office space they occupy by squeezing their employees into smaller offices or cubicles, often half the size of their previous one. A halficle is a half-sized cubicle.
To save money, our company downsized everyone's cubicles to halficles. Jan is only 4'9" and she can lay across her halficle work surface and touch opposite walls! Our new halficles are so small, I can reach over and answer my neighbor's phone without leaving my chair!
The act of checking your iPhone with the intent to do one thing and being so distracted by notifications from other apps, texts or messages that you forget why you checked your phone in the first place. Can happen with any smartphone.
Sorry I didn't call you back, but by the time I updated my Facebook status and answered some texts my iPhone ADHD kicked in and I forgot what I was doing.