A way to track important dates and milestones within the game

I was thinking just now I wish I could remember when I upgraded to TH9 and how long it took me to max out....how long did I spend between TH8 and TH9....how long has it been since I first started COC. Even track the date of all achievements you receive within the game. And so on.
It would be great if there was a calender, or just something that kept track of certain milestones reached and significant upgrade completions by date so we can all look back and reflect on that specific date and time!

Google playe and/or game center track achievements.