Chapter 3. Designing Online Behavior

Now that we have built an offline to-do app, let's go one step further and decide what the full online experience will be. As we progress, our goal is to migrate the app to the Internet without compromising its offline behavior.

It's useful to think about this in terms of a bunker and beach house analogy. An offline-only app is like a hardened bunker: invulnerable to what's happening above the ground but quite isolated. It's not a place you'd want to spend all your time, though you'll be glad to be able to retreat there when necessary.

An online-only app, in contrast, is more like a beach house. It's bright and cheery; the kind of place you'd want to invite your friends to hang out. However, if an earthquake or tsunami should happen, you'll quickly forget about all the nice aspects of your building as you flee for the hills.

What we're trying to do is marry these two concepts and create a hybrid...