Notification Cron - This is a great way to use your phone for reminders and learn Quartz Cron.
SunTimes - This app will set alarms at certain sun/moon points in the day. So whatever time sunrise is at your location an alarm can go off. I like to use it to let me know when Golden Hour starts and the day is almost ending.
QuillNote - I love this note taking app, and have taken to posting thoughts there to lower the number of tweets/posts I send. I get the dopamine rush of typing out and saving my thought, and it all stays local.
Mindful Notifier - Whenever this bell goes off (and I set it random between 90 minutes and 120 minutes) I take three very deep breaths. The sayings are okay, but the healthy intake of oxygen is great.
SMS Scheduler - An older app, but a great way to send a text at a later time. My daughter has a different work schedule than I do, so I schedule texts to her for when work is done. Also, if someone asks me to remind them of something later, I schedule the text and it sends as a reminder.
Dodge - Simple game of getting across the screen. My record is 13.
Snotz - I like this for non-thoughts (Quillnote) but tend towards quillnote more. It's a note taking app with nice colors.
FOSS Browser - This is a nice simple browser for when I don't want to be tracked.
Nunti - Pretty good feed reader that supposedly uses AI to tell what stories to share. I'm still training it, but prefer it over online news aggregation.
Vector Pinball - I played this game longer than I should have.
1list - great shopping list app, or any other list you may need to make, and all stays local.