Alternate Keyboards in iOS: LetMeSwitch is a Cydia tweak that allows those who have multiple keyboards installed switch between them with just the press of a button.
Download and Install LetMeSwitch Cydia tweak
You can get the LetMeSwitch Cydia tweak for free through the BigBossRepo. Those who have numerous keyboards on their computer and want the ability to switch between them will definitely find this tweak to be incredibly useful. This will work fine on any iPhone / iPad / iPod touch running on jailbroken iOS.
Search for LetMeSwitch on Cydia Search tab > tap “Modify” > tap “Install” > tap “Confirm” > Restart Springboard.
Open Messages app > Simply press and hold the globe button at the bottom of your keyboard and you will be presented with a full list of all the keyboards that you have installed on your device currently.
While regular third party keyboards only allow you to go to the next keyboard, this one is much different in the sense that you will be able to see all of your keyboards and switch between them extremely quickly and easily.
All you have to do is install this tweak, hit the globe icon and select the keyboard you want to use. Make sure to respring your phone once you have this tweak installed to make sure it works with all of your keyboards.