iOS app taking looong time to load

since several months the app will freeze often at opening, or take a long time to load, like 3 minutes, if it doesn't crash. this on fast internet wifi connection. It is sometimes helped by shutting down the app, but not always. It makes it impractical to use the app. I am reverting back to using the online web browser version. I prefer using the app like it works fine last summer.

iOS 10.2 on iPad Mini 2