Just back from Budapest, Vienna and London. Will post other reports on their respective boards/threads. We ended up in Vienna on the weekend. A number of places were closed on weekends and others which said they were open on weekends were closed on that particular weekend. We found food but had some two-meal days. We got groceries for breakfast in the hotel room as we generally do when traveling.
We're both vegan and I'm gluten-free. Took along the German explanation of gluten-free diet from www.CeliacTravel.com which came in handy. Ate twice at Bio Bar von Antun. Good food, all vegan, GF desserts labelled. Also ate at Naturhost St. Josef and got some groceries. Had vegan food, found someone from the store with some English which combined with my German, we able to determine what was GF. Ate at Aromat, where unfortunately, they allow smoking in the restaurant. Again, able to determine what was GF using the printed info in German and my limited German.
No fridge in our hotel room so other meals consisted of rice crackers with vegetable spread, juice, rice cakes with peanut butter and jam, GF cookies, etc.