I switched to Apple in the end of last year and I was able to download the app then. It's not great, but it does work, sorta. You just have to be patient and not try to do too much with it.
Tapatalk created the old TBN app. You can use tapatalk, but it sucks. All ads. On a phone screen all you see is one post and ads. It makes TBn unusable. Now I resort to a browser. The old app was great.