If you have a new device with Android’s stock keyboard or you happened to install the Google Keyboard standalone app on your device, but you thought you liked one of the older style themes, we have some good news for you. Apparently Google never bothered to remove the “theme” code from previous versions of Android as the keyboard app has matured over time and these old themes, and one other, can be accessed with a little work on your part.
To get to the settings to select the theme, you will need a replacement launcher installed. Something like Apex or Nova will work well, but any launcher that gives you access to “Activities” will suffice. With an appropriate launcher installed, long press on the homescreen and head to Shortcuts. From there, select Activities, and then find the Keyboard activity. This may be named Google Keyboard or Android Keyboard (AOSP) depending on your Android version and device. From there, select the Android Keyboard Debug Settings. All of this is to create a shortcut on your homescreen to access advanced settings.
Once the shortcut is on your homescreen, tap on that and then find the setting for Theme. You should have a total of six choices to choose from – Basic (normal), Basic (High Contrast), Stone (normal), Stone (bold), Gingerbread, and Ice Cream Sandwich. The Basic theme is what was used prior to Gingerbread and Ice Cream Sandwich is the current theme used on ICS and later versions.