If you try to edit an article in the iOS Wikipedia app when you’re IP blocked, it will allow you to revise the article but not to save the changes. This is a very frustrating user experience since you can potentially spend a long amount of time editing a page to find out you’re not allowed.
I disagree with Wikipedia’s policy that, even if you’re logged in, you can’t edit from a blocked IP. But the least you can do is tell me upfront before I sink time into editing a page. The desktop site does this correctly—it shows a large message that you can’t edit Wikipedia and the read-only wiki text.