1. Pihole to ad block ads (useful for phone browsing) https://pi-hole.net/
2. Custom Weather conditions dashboard, using Dark Sky's API
I'd love to replace the weather dashboard with one of my integrated work / personal calendars so I could see what meetings I have each day but work won't expose that data, claims it's a security risk.
3. Custom NYC subway dashboard, showing me estimated train arrivals for trains at the 2 closest stations.
The MTA has free apps which also show estimated train arrivals but only for one station at a time. Also, the MTA's train estimation methodology isn't as accurate as it could be.
4. Retro Pie, to play NES and SNES games https://retropie.org.uk/