Code Editor is the best code - text viewer and editor for Windows10 and Windows Phone!
The application provides, in addition to the Viewer, two types of editors: Simple Editor is designed for changes on the fly, the Advanced Editor is able to check language syntactic error and provides more advanced features like code highlighting, undo, redo and search capability.
There are 3 themes for both viewer and Advanced editor: light - grey - dark.
The application allows the user to get files from OneDrive, DropBox (directly from within the application), browser and load files directly from the device's file system.
When a file is opened for editing you can actually press "save" to overwrite the current version, or select "save as" for more options.
The settings page allows you to enable/disable line numbers and other options.
The most common file types supported are: txt, asm, cpp, cs, py, rb, java, php, vb, basic, logs, config and many others. To get started just create a new file, obtain one from the internet, or by mail. After that you can sort them, edit them and share them with friends and colleagues via sms, email, social, One Drive and Dropbox! (press and hold on the document for more options).

The application is localized in various languages, if you'd like to improve the translations please contact me!