Source: http://www.engadget.com/2014/10/22/twitter-trades-passwords-for-phone-numbers-with-digits-login/
At its mobile developer conference in San Francisco, Twitter just announced Digits, a brand new way to login to apps with just your phone number. Instead of going through the tedious process of signing up with an email and password or using one of many different social logins, all you need is to enter in your number. When you do, you'll get a confirmation code via SMS. Enter that in as well, and away you go. Digits is not based on your Twitter account at all; it's actually an entirely new product that developers can incorporate into their apps. It's a key part of Fabric, Twitter's new mobile development kit that it's rolling out today. Digits is available for iOS, Android and the web, and it's available in 216 countries in 28 languages from day one.
Aside from Digits, Fabric includes several other tools that Twitter hopes developers will incorporate into their existing apps, such as Crashlytics, the crash reporting tool that the company bought last year. Especially of note is that developers can now not only embed tweets in their apps, but also the ability to compose and post tweets inside of them without having to launch the dedicated Twitter app.
Developing...
Source: Digits