One of my favorite tweaks is NudeKeys by orangebananaspy.  This dev puts a lot of his own time to develop many tweaks for free.  With Nude Keys you can customize your keyboard.  The possibilities are endless.  I helped this dev back on iOS 9 days with testing and even making keyboards for his application.  

You can find NudeKeys on his repo repo.orangebananaspy.com  There are also a lot of pre made keyboards on his repo.  The hard work and professional craftsmanship really shows.  Buy this man a beer.  You can donate once the tweak is installed in the preferences, or donate here.  Pay Orangebananaspy using PayPal.Me Go to paypal.me/orangebananaspy and type in the amount. Since it’s PayPal, it’s easy and secure. Don’t have a PayPal account? No worries. paypal.me