How to Enable/Disable iPhone Keyboard Auto Correction

I tried to install "Tweaks (1.1.1) > kb2" for a few times but didn't work - could not download package. Finally, I tried "Toys > kb", it installed, the option appeared in the keyboard settings but erased the last 2 options: ". shortcut" and "International" and the ". shortcut" was not active anymore. I've disabled the option for auto-correction, it works OK, but now I can't activate the ". shortcut" anymore. Finally, I've uninstalled the "Toys > kb" utility, the auto-correction remained DISABLED and the settings option dissapeared, the last 2 options re-appeared, but enabling/disabling the ". shortcut" option has NO effect. Is is no more active ! Do you have a fix for this ? Or do you think I'll be able to install "Tweaks (1.1.1) > kb2" and repair my problems ? Please advise.