I know I should post in suggestions, but meh. My suggestion is that when your elixir runs out, you get a notification at the top right corner of the screen, saying your elixir has run out. Once you tap the message, you have the option to rebuy the same elixir right from your playing screen, saving time and stress in the middle of the run. Hopefully a dev reads this because I really think this is a worthwhile idea. Thanks.