After using email to blog for a bit over a month now, I’m convinced that email and SMS should be considered first class citizens when designing a new software product. There are two reasons for this.
When you allow email and SMS to be a primary interface, you are absolving yourself of entire classes of problems during development. Everybody will have email or texting capabilities from their phone. Your users will already be familiar with email and texting, and do not have to download your app, learn a new UI, or worry about remembering another username and password. Both email and SMS are resilient to bad network conditions, and are inherently accessibly by design. This frees you up to focus on a well made mobile web app for the more complex, but infrequent workflows. While there are downsides to text only interfaces, I think it’s a development avenue not enough developers take seriously.