Pythonista 3 Python Interpreter for iOS
Python is one of the most popular programming languages around. Whether you want to program Raspberry Pi projects or just teach someone programming, this is a solid language to use. With Pythonista 3, you can edit and run Python scripts on your iPhone or iPad.
Pythonista 3 is a Python editor with syntax highlighting and code completion. The app also shows command history and has a visual debugger. You get light and dark color themes and can customize the editor to your liking. There is also a UI editor for quick prototyping.
Pythonista 3 supports both Python 3.5 and 2.7. Plenty of third-party modules are covered.