The Best Crochet Apps and Software

Dear users and authors,
do you use crochet apps or related software? What has your experience been like?

Please do not post external links. Thank you. 

I think ZählMich is very good. You can upload your patterns there. The app has a row counter, stopwatch, notes… and I think you can also write your own patterns.
You can also convert things :)
The app costs a bit, but it’s worth it

Nevertheless, I’ve now switched to Knit&Note :) There, you can not only upload patterns but also enter and organize your stash. You can then link the yarn entered there to projects/patterns. That’s missing from ZählMich (it’s there, but not fully developed. For me, the app has been freezing a lot ever since)

Both are really great apps that I wouldn’t want to be without!