Hi @tony_ventiquatt -
Canvas Student 6.12.0 for iOS was released July 26, and Canvas Student 6.13.0 for Android was released July 14. These are the current versions for the Canvas Student app.
One thing to check is the operating system of your devices.
I know that you initially posted five days ago, so early next week when you're with students again, how are things? Is it a universal experience, or is it just some of your students who have the lagging with the app?