As I discussed in a previous post, Heidegger thought that typewriters are "signless clouds," and that the hand was essential for thinking. So, it might be thought that he was entirely opposed to new technology in writing. This would be wrong, however, as he did adopt fountain pens. While he seems to have used dip pens, steel nibs, and inkwells when writing Being and Time, he later clearly (also) used fountain pens.
Photographs show that he later used fountain pens. There is a Web site that claims that he actually used a Kaweco Elite. "The Elite was Kaweco’s top of the line and enjoyed a special embossed pattern of stair-step lines that add both grip and visual interest to this pen ... I have a photograph of Martin Heidegger writing with a Kaweco Elite and writing with this pen has always given me the covert joy of using something very special that most folks would never recognize as such." This is possible, as Kaweco was big around 1925, though it declared bankruptcy in 1929. But around 1930, "230 workers produced the Kaweco -Kadett, -Colleg, -Dia, -Elite, -Carat, -Schulkaweco, -Helios and again the Kaweco- Sport."
I have seen quite a few photographs of Heidegger's writing desk, but I cannot make out the precise looks of the pens on it. The resolution is just not great enough. It does appear to me, however, that he used more than one type of fountain pen. In any case, if you believe that the writing instrument determines what you think, then Heidegger may have produced Kaweco philosophy. But even I would not attribute that kind of thing to this controversial thinker. Just look at this:
1. Thus, when he speaks in §15 of Being of time of "Schreibzeug" or writing "tools," he mentions "Feder, Tinte, Papier, Unterlage, Tisch ..." (nib, ink, paper, writing surface, desk ...). While this list does not prove he did not use a fountain pen at that time, it does indeed suggest that he was still using inkwell and dip pen. In any case, this practice would not have been unusual in 1925/26.
2. See here for more details.