A good T-Mobile phone? Suggestions?

I kind of miss my old candy bar (dumb) phone. It was durable, the battery lasted a week before needing a charge, it wasn't as huge as a smartphone and it wasn't so much of a distraction as my current smartphone is either.

Sticking with Nokia, I ended up with a Nokia Lumia 925 Windows 8 smartphone. It's been a good phone, but it's starting to act up. However, looking at T-Mobile they have no more Nokias, and I'm just not sure what to get.

I like my smartphone mainly because it has Wi-Fi calling. Too bad there isn't a "dumb phone" with Wi-Fi calling or I'd get that!

So what would be a good small, durable, good battery life phone, with Wi-Fi calling, that would work with T-Mobile and not cost an arm and a leg?

All answers appreciated.

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