Nexus S
Unlocked with CWM running CyanogenMod 10.2.0 stable
Nexus 4 (sold)
Nexus 5
Unlocked, TWRP as custom recovery running CyanogenMod 13.0 snapshot
Nexus 5X
Unlocked, TWRP as custom recovery. Running rooted stock Android 7.1.x ;-D
Nexus 7
Unlocked, TWRP as custom recovery. Running rooted stock android 5.1.1.
ClockworkMod (on both Nexus S and Nexus 5)
TWRP is the recommended custom recovery (Nexus 5X)
NOTE: I missed some of the apps when moving away from Android back to iOS after the Nexus 5X bricked.
Greenify (root required, 2.0+ does not require root but auto hibernate won't work)
Titanium Backup (root required)
Termux (Terminal Emulator and Linux Environment - apt and a repository of powerful GNU CLI tools aarch64).
iSH + Alpine Linux (iOS, x86, emulation via QEMU)
strongSwan VPN Client (IPsec VPN client - native)
WireGuard (iOS)
Xposed framework + XPrivacy (root)
Android Terminal Emulator (root)
SSH Server / Rooted SSh / SFTP Daemon (root)
SuperSU (built-in in CM, root)
ES File Explorer File Manager
Nova Launcher (my favorite)
KWin ;-)
Materialistic - Hacker News client
Octal (iOS)
tldroid - TLDR android client
tldr-pages (iOS)
CatLog