Previously, it has worked for me great and I was also able to use the Blynk IoT app on my iPhone.
Recently, I got an update on the iOS (Blynk IoT version 1.20) and it broke blynk for me.
I still can login to lon1.blynk.cloud, but there is no way (in the app) to switch servers manually. I believe there was an option to switch servers in the Blynk IoT iOS app previously.
There is no way to switch servers in mobile app. On login attempt application resolves which server has the user account. So, what happens when you try logging in the app?
When I try to login it says: Email and password is incorrect. Please double-check and try again.
This is odd since I can login on the web just fine with same email and password.
Here is some more info that might help:
I can login on lon1.blynk.cloud just fine.
When I try to login to blynk.cloud or Blynk IoT app for iOS (or android), I get an error that tells me to double check my email and password and try again.
Another iOS device that is running an older version (1.1x) of Blynk IoT app works just fine with same email and password.
I have deleted the app and reinstalled it, but this did not work.
I also tried to clear my browser cache but that did not seem to work either.
On iOS, first go to System Settings → Blynk and enable logging there. Launch Blynk app, try to login. Go back to initial screen, tan&hold on Blynk logo → About screen will appear. From there you can send logs.