This app was mentioned in 2 comments, with an average of 1.50 upvotes
https://play.google.com/store/apps/details?id=com.colab.azix.timekit
noob app i made a while ago. countdown everything! No notifications though =( (set an alarm)
they did. somewhere. you can also download my wonderful noob app with no notifications and that doesn't run in the background, meaning you have to keep checking how much time is left till the event. But... it has a countdown feature...
https://play.google.com/store/apps/details?id=com.colab.azix.timekit