One way of doing it is having an out-of-bands way of refreshing tokens in responses. So if the token is about to expire you can return an updated one on the side-channel.
Go doesn't really work because it needs a runtime (as far as I know). Rust however is quite useable. There's a couple of kernels, including one by me: https://github.com/lexs/rust-os
And the app doesn't look native to Android either. Some things are inherently non-Android, such as bottom tab-bars. All images are also low-res on my Galaxy Nexus and scrolling is laggy.
There are some great bugs as well:
* It loads the wrong images and the flickers in the correct image later
* Everything says "0 listings"
* Clicking the map button crashes the app
* It's very hard to sidescroll their custom ViewPager