Development mode
Development mode is a feature on the user interface that serves both as a debugging tool for developers and as a cheat menu for most other players.
When active, it is seen as an additional menu on the top of the screen.
Features
Items are shown from left to right in the picture.
Debug log
An output log for debugging. Shows errors if they occur, as well as debug outputs.
Package editor
It allows you to edit game data while the game is running. Currently limited to sound and colonist hairstyles.
View settings
Toggles special debug visuals, such as shooting hit chances, infestation chances and toggling fog (fog of war) and snow visibility.
It also allows some debug settings, for example, unlimited power, toggling damage, and fast research, learning (i.e. instant boost to lv 20 upon doing a task), ecology, crafting, caravans, etc.
Forces a variety of things to happen. Many things can be done from here; spawning items and pawns, executing events, downing/ killing pawns, they are all done through this menu.
Where some debugging information can be found, like crop economy, item nutrition, and such.
Inspector
Lets you see what's happening in the game.
God mode
Toggles god mode. While active you can build structures instantly at no price and research. Godmode can be also toggled through 'View Settings'.
Godmode persists even when development mode is turned off.
Autopause
Toggles autopause when an error is logged.
Save translation report
An option shown on the title screen, it generates a report about the currently-loaded language data stating which translations are missing, which are unnecessary, and other useful information for translators.
Options
Permanently disable
In the Options menu in-game, you have the choice to 'permanently' disable development mode. This prevents you from cheating using this.
You can reset it by deleting the 'DevModeDisabled' file can be found in the config folder
It can be retrieved through: Start+R > appdata > LocalLow > Ludeon Studios > Rimworld by Ludeon Studios > Config.