It's a great idea and I can see a lot of people using such an app. But I don't feel like it's really productive, or even healthy to look too much at the past. Reminds me a quote "if you spend your day thinking about yesterday, what will you do tomorrow?"
Good point. Just another way of looking at it though. Looking back in life from a perspective of 'hey things are actually pretty great in my life' is good for the mind. It actually gives you reason to look forward to the moment. There is of course the possibility one might look back and say I wish my life was more awesome like back then. But given that the wins would be like something from yesterday or the past week, I think the odds of the brain thinking that way might be microscopic.
