As far as I know, 'Taschnermeister' is a professional title — 'Taschner' is a leatherworker/bag-maker, I believe, and the -meister suffix in German is used to indicate skill or seniority in the field (a master craftsman).

'Wien' is the German name for Vienna, and Am Spitz 2 is a street address. It looks like Nazi postmarks/date styles used Latin numerals for the month, so 16.III.38 becomes 16 March 1938. I don't know what the .21 at the end would connote, and I can't make it out from your pictures. 'Der Führer in Wien' — 'The Führer in Vienna' — is a cachet; a commemorative inscription.

(Here are some contemporary examples from which I'm drawing those conclusions.)

Hitler annexed Austria in March 1938 (the Anschluss); German troops crossed the border on 12 March, and Hitler gave an important speech in Vienna on 15 March, so the chronology would seem to match up pretty neatly with the date mark.

It looks like the postcard dates from the very last days of Austrian independence — I can't read the handwriting, unfortunately, so can't tell you what the pencil markings say. Someone else might be able to help more.

Pictures fixed after request!