It's quite remarkable to me how many services I have been able to replace with self hosted ones (a big thank you to this sub for that) and open source apps.

• Photos - Immich
• Movies - Jellyfin
• Documents - Paperless ngx
• Podcast - Audiobookshelf
• eBooks - Calibre web
• Music - Jellyfin (Finamp app)
• Read Later - Wallabag
• RSS - FreshRSS (with Read You app on Android)
• 2FA - 2FAuth
• Passwords - Bitwarden (hopefully I'll switch to Vaultwarden someday)
• Finance - Firefly III
• Notes - Joplin (with self hosted Joplin server)
• VPN - ProtonVPN
• Personal blog - Memos (with MoeMemos app on Android)
• YouTube - NewPipe (I hope we get to see a real alternative to YouTube someday)

However, there are still apps and services which I have not been able to replace with self hosted ones and open source apps.

There are:

• Open source PDF reader and editor - I can't seem to find any alternatives to closed source apps for this on Android, nor is there anything like it in the self-hosted space (Stirling PDF cannot store PDF documents nor is it very good at annotating. It's great at conversions which is what it should be used for)
• Office apps - Even though I am not looking for something as polished as Microsoft Office, there are still no options other than Libre Office for Android whose document editing features are at a very alpha stage. Self-hosted Only Office or Libre Office through Kasm VNC do not work well on mobile.
• Tasker for Android - there's nothing like it in the open source sphere
• Folder Sync Pro - One way sync from mobile to NAS to backup photos. This is in addition to Immich doing its own thing. (Folder Sync is basically Rsync, but because it can run in the background on mobile, it's so much better than anything else right now). Syncthing cannot do one way sync
• Yahoo Finance - A tool to track prices of stocks. I don't think there's anything like it in the self hosted space or on Android which is open source.