Senn makes the point in his blog that if our devices could feel, they would be nervous wrecks, constantly terrified of replacement. In today's age of rampant consumerism, the product life-cycle of our hardware is dramatically shorter than it should be. Senn takes a funny approach by anthropomorphising a smartphone into a needy insecure partner, which gets his point across well. If your couple-years-old phone could talk, it would likely plead for mercy, begging you not to throw it away. While Senn gives valid reasons for why our devices would feel jealous or even terrified if they could feel, what interested me about this angle isn't really addressed in the "face-hugger" concept. I think this idea veers more into the territory of revenge more than envy. There's something sinister about a creature that sticks to your face and limits your field of view. As if your implied threat of replacement has put you in its crosshairs, and it's not letting go...
Senn applies a desire "to be indispensable, irreplaceable" to his creature. I would argue this reflects more on us as consumers than on our devices. A creature that displays jealousy for you, the viewer, would act aggressively, maybe even violently toward the thing that is taking your attention away from it. It wouldn't act like that toward you. You could demonstrate it by having multiple creatures competing for the viewer's attention somehow, and clashing with each other if they notice their peers are getting more attention.
Picture NVS & JLS: simple constructs consisting of a head on a swivel with eyes, eyebrows and a slapping hand. The eyes are cameras that recognise two things: the viewer's eyes and each other. They track the viewer's eyes and, depending on where he's looking, will emote with their eyebrows. If NVS is to the left of JLS and it notices that the viewer's eyes are spending an awful lot to the right of it, it frowns, turns 90 degrees and slaps JLS right in the noggin'. Same goes for JLS.