Sorry for the slow reply, thought I was so far down the list people wouldn&#x27;t be seeing it.<p>First - thanks for the feedback and discussion. Really useful insights.<p>You are correct in that the interface is the &#x27;new&#x27; - and also that single codes are a poor way of input. The original reason for SMS was to interupt the user to actually get them to make a measurement. I&#x27;ve since changed that the interupt still comes as a message, but the input&#x2F;logging is done through a full application. It also means that the application is more accessable for reviewing data, making changes, processing, etc - as you mention is an advantage for simple spreadsheets.<p>The advantage over a spreadsheet is trading some &#x27;freedom&#x27; for easier analytics. I&#x27;m wanting to make quantified self more accessible for people without the skills (or maybe interest) to do data processing themselves.<p>Agreed that having a smartphone is probably a good assumption for the market.