DroidVim is a Vim clone text editor ported for Android.
Vim 8 (huge version multi language) grep diff and ctags are ready to use.

▼ Required - ARM (Android 4.1 and up) x86 (Android 4.3 and up)
Features:

▼ External storage support - External SD card USB memory GoogleDrive Dropbox etc. (Requires Android 4.4 and up)
▼ Special Keys - Esc Ctrl Tab Arrow keys and more.
▼ Direct input - Disabling predictive text and/or auto correction for normal mode.
▼ Clipboard - Clipboard commands ("*p "*y) are supported.
▼ Custom Font - Use your favorite monospaced font.
▼ Touch to move - Touch swipe flick to move cursor.
▼ Multi language - Vim with multi byte option iconv and multi language messages.

Extra features (in-app purchase):
▼Git - Version Control System.
▼curl - A Tool to upload/download files.
▼Busybox - A collection of UNIX utilities that do not exist on Android.

Tips:
▼ Tutorial - Type ":Vimtutor".
▼ You can change the keyboard input mode from Vim script.
It is possible to disable word suggestions in normal mode and enable word suggestions in insert mode.
- https://droidterm-e8a40.firebaseapp.com/droidvim/index.html#imctrl

Troubleshooting:
- If Vim freezes tap "close window" on the menu.
- If you got keyboard input issue change "Input method" preference to "Character-based" or use another keyboard.

Appendix:
DroidVim is an open source project.