It’s called Foxlet - it used to be called Stellar Desktop Client. It’s not “official” but it’s pretty good and I personally haven’t had any problems with it.

Yes, I agree - they shouldn’t have made your federated address your email, instead we should have been given a choice at the onset. Maybe they will change it. Send them feedback saying so. They are listening to the feedback, so here’s your chance to be heard.

I don’t know why it took you so long to figure out how to close your trust line. It’s right there in your Settings > Stellar Network > Close. Done. It’s new. There’s a learning curve. You figured it out. Now you know.