This is incredible - the first full-featured game made for not just the TC-06 architecture, but the default mode version that has 128 bytes of RAM and a 1kB drive? Mind blowingly cool. Played in a Custom mode preset with some different colors, and a 1kHz clockspeed to have more than 0.15 frames per second? It's a proper Snake game, complete with the real tension of needing to make decisions on the fly. I do not have words for the levels of cool. Also, naturally, I'm absolutely terrible at it. >.<
I found what I initially thought was a bug while trying to do some fancy maneuvering around a food item, but I think it might just be that I ran into myself. I don't think there's anything to stop you from turning in the direction you came from - e.g, going left to right, trying to change direction to be right to left functions just fine, and in a buttonmash panic, it's very easy to do this and get a game over.
I think you officially qualify as being better with the TC-06 than I am. I haven't done anything nearly as cool as this, my main specialty seems to be planning out grand ideas that I'll never actually get around to implementing. >_<