I tell my teams to measure a storytelling of 10s. In the first 10 seconds they have the phone, do they understand what they are getting? Then the first 10 minutes: Is it easy to engage with the product, do a simple task? At 10 days, are they frustrated with the product or telling their friends about it? What are they starting to discover? At 10 weeks, what are the powerful features they didn’t use before? Are they putting folders and widgets for their own stuff in the phone? At 10 months, they may be ready for a change. Did your brand fulfill its promise, so they stay with you?
I think we need a model like this for software. Any ideas?