First I have to say... WOW. The video is great! Whoever did that has a lot of talent! It has style, it is clean, and shows enough to get you very excited. Please make a video for bitcoin itself of that quality!!
Is this device even possible? YES. Just barely and with some tricks. Can it do everything shown in the video practically and in the real world.. no. But it can do most of what is shown and if made (if it has not been made already) will be a great boost to bitcoin and it's makers/investors. COINLAB ARE YOU LISTENING?
My rough guess as to the specs/device:
CPU: something in the ballpark of S3CT9KW. Maybe 4x better but probably not.
RAM 144KB
ROM 320KB
CPU speed 5Mhz
Display:
flexible epaper
Due to these choices of a super low cpu speed and super low power usage on the display the device can run off of solar power and/or tiny battery. With this level of power the device could SEND and hold bitcoins. It could accurately display a balance of what is held IF the keys were not held elsewhere because it knows what it sent out.
What can it not do? Receive bitcoins and know the balance accurately. It could talk to a central computer for that, but the device is not going to be able to hold the blockchain or process it on its own. Still this is good enough!
Texting/display:
This is all possible. The device could communicate with others near it or more realistically communicate to a base station that did the relay work. A commodore 64 could run a full BBS, a device with 4x the power could easily run a texting service. Coupons, offers and ads could be delivered as shown.
Tracking:
Of course. This is pretty easy. The base station is doing all of the work. The card is just providing a beacon and a GUID.
Mesh:
This is where the device breaks down. Mesh has been the most over exaggerated area of computing I have seen. Mesh stuff simply does not work that well in the real world. The device could communicate with others nearby and form a mesh.... but it would not have the power to keep up that mesh all of the time. With devices being in peoples pockets and not getting much power, the mesh would not get the density it needed except in a crowded space with many users all holding them up to the light.
Now base stations all over the place would fix this. And this might be possible do to with a very low cost base device. But the mesh is going to be formed by the base stations, not by the cards.