Mobile phones have increasingly been transformed from speaking technologies to devices for reading and writing. Cost helped drive this shift since written short messages were historically less expensive than voice calls. A second factor was communication preference for texting over talking, especially among younger users. With ready Internet access on smartphones, reading habits began shifting as well. Social networking messages, along with other short texts such as weather reports or news headlines, made for obvious reading material, as did the plethora of longer written documents available online. The e-book revolution enabled readers to retrieve entire books on their phones. Mobile phones are also writing platforms. Developments in hardware and software dramatically simplified the input process. Instead of multi-taps, users now rely on virtual keyboards for easy access not only to alphanumeric characters and punctuation marks but also to sophisticated predictive texting and autocorrection. Interestingly, while technically we are writing when inputting text on smartphones, many users do not perceive such input as real “writing”—a term they reserve for writing by hand or with a computer. Additional writing issues include norms regarding so-called textisms, along with the role of culture in shaping attitudes regarding linguistic correctness. Many organizations are discontinuing voicemail systems in favor of written messaging. At the same time, voice over Internet protocols continue to grow, and small voice-activated social robots designed for home use are proliferating. The chapter closes by asking what the spoken–written balance on smartphones might look like in the future.