my iPhone's systemwide font has changed automatically!

[FSBW21086]

the default systemwide font is helvetica. Every time I went to make a phone call the phone app crashed. When I rebooted the phone the systemwide font has changed to arial! Can't find much info on this online

[Pixellated]

Have you got 'Kate' installed from installer? Uninstall it and you'll be good.

[FSBW21086]

thank you.