Reports: Twitter’s sudden third-party client lockouts were intentional

I'm guessing it's about the ad revenue; most third party apps don't show ads.

Not familiar with the app, but the Twitter web interface is bloated and awful and hides a bunch of stuff if you're not logged in. I use the Libredirect addon which redirects a number of services to privacy frontends, in Twitter's case it redirects to nitter - example nitter instance. It doesn't let you login to a Twitter account or post, but works fine for me. If nitter stopped working I'd stop seeing Twitter content altogether.

Fritter is another Android app that still works, but like nitter it only lets you view content, not login or post.