I love Twitter this way, which is built "offline first". Twitter will let you read everything in your timeline that you have previously downloaded, let you rep

I love Twitter this way, which is built "offline first". Twitter will let you read everything in your timeline that you have previously downloaded, let you reply to and like as many tweets as you want, and never complain about lack of connectivity. It'll just dutifully queue your requests and act on them once you're back online. It's one of the only connected apps properly usable on the subway.